diff --git a/assets/javascripts/discourse/components/param-field.js.es6 b/assets/javascripts/discourse/components/param-field.js.es6
index 89d1192..17dfb37 100644
--- a/assets/javascripts/discourse/components/param-field.js.es6
+++ b/assets/javascripts/discourse/components/param-field.js.es6
@@ -4,5 +4,5 @@ export default Ember.TextField.extend({
       this.get('params')[this.get('pname')] = value;
     }
     return this.get('params')[this.get('pname')];
-  }.property()
+  }.property('params', 'pname')
 });
diff --git a/assets/javascripts/discourse/controllers/admin-plugins-explorer.js.es6 b/assets/javascripts/discourse/controllers/admin-plugins-explorer.js.es6
index 1a74ec2..47ffd0c 100644
--- a/assets/javascripts/discourse/controllers/admin-plugins-explorer.js.es6
+++ b/assets/javascripts/discourse/controllers/admin-plugins-explorer.js.es6
@@ -137,14 +137,17 @@ export default Ember.ArrayController.extend({
           explain: this.get('explain')
         }
       }).then(function(result) {
+        self.set('results', result);
         if (!result.success) {
-          return popupAjaxError(result);
+          self.set('showResults', false);
+          return;
         }
 
-        console.log(result);
         self.set('showResults', true);
+      }).catch(function(result) {
+        self.set('showResults', false);
         self.set('results', result);
-      }).catch(popupAjaxError).finally(function() {
+      }).finally(function() {
         self.set('loading', false);
       });
     }
diff --git a/assets/javascripts/discourse/models/query.js.es6 b/assets/javascripts/discourse/models/query.js.es6
index a6bb643..2c965c3 100644
--- a/assets/javascripts/discourse/models/query.js.es6
+++ b/assets/javascripts/discourse/models/query.js.es6
@@ -5,10 +5,20 @@ Query = RestModel.extend({
   dirty: false,
   params: {},
 
+  _init: function() {
+    this._super();
+    if (!this.get('options')) {
+      this.set('options', {defaults:{}});
+    }
+    this.set('dirty', false);
+  }.on('init'),
+
   _initParams: function() {
     this.resetParams();
   }.on('init').observes('param_names'),
 
+  options: Em.computed.alias('qopts'),
+
   markDirty: function() {
     this.set('dirty', true);
   }.observes('name', 'description', 'sql', 'options', 'options.defaults'),
@@ -37,7 +47,11 @@ Query = RestModel.extend({
     const currentParams = this.get('params');
     let defaults = {};
     (this.get('param_names') || []).forEach(function(name) {
-      defaults[name] = currentParams[name];
+      if (currentParams[name]) {
+        defaults[name] = currentParams[name];
+      } else {
+        delete defaults[name];
+      }
     });
     this.set('options.defaults', defaults);
   },
@@ -80,7 +94,7 @@ Query = RestModel.extend({
 });
 
 Query.reopenClass({
-  updatePropertyNames: ["name", "description", "sql", "options"]
+  updatePropertyNames: ["name", "description", "sql", "qopts"]
 });
 
 export default Query;
diff --git a/assets/javascripts/discourse/templates/admin/plugins-explorer.hbs b/assets/javascripts/discourse/templates/admin/plugins-explorer.hbs
index c34c7e5..3d1396f 100644
--- a/assets/javascripts/discourse/templates/admin/plugins-explorer.hbs
+++ b/assets/javascripts/discourse/templates/admin/plugins-explorer.hbs
@@ -1,24 +1,38 @@
-<h3>Queries</h3>
+<h2>Queries</h2>
+
 <div class="query-list">
   {{combo-box valueAttribute="id" value=selectedQueryId nameProperty="listName" content=content castInteger="true" nameChanges="true"}}
   {{d-button action="showCreate" icon="plus" class="no-text"}}
   {{d-button action="importQuery" label="explorer.import.label" icon="upload"}}
 </div>
+
 {{#if showCreate}}
   <div class="query-create">
     {{text-field value=newQueryName placeholderKey="explorer.create_placeholder"}}
     {{d-button action="create" label="explorer.create" icon="plus" class="btn-primary"}}
   </div>
 {{/if}}
+
 <hr>
+
 <div class="query-edit">
   {{partial "admin/plugins-explorer-show" model=selectedItem}}
 </div>
+
+{{conditional-loading-spinner condition=loading}}
+
 <div class="query-run">
   {{#if selectedItem.param_names}}
     <div class="query-params">
+      <div class="param-save">
+        {{d-button action="saveDefaults" label="explorer.save_params"}}
+        {{d-button action="resetParams" label="explorer.reset_params"}}
+      </div>
       {{#each selectedItem.param_names as |pname|}}
-        {{param-field params=selectedItem.params pname=pname}} {{pname}}
+        <div class="param">
+        {{param-field params=selectedItem.params pname=pname}}
+        <span class="param-name">{{pname}}</span>
+        </div>
       {{/each}}
     </div>
   {{/if}}
@@ -27,10 +41,17 @@
   </div>
   {{d-button action="run" label="explorer.run" disabled=runDisabled}}
 </div>
+
 <hr>
-{{conditional-loading-spinner condition=loading}}
+
 {{#if results}}
   <div class="query-results">
-    {{query-result query=selectedItem content=results}}
+    {{#if showResults}}
+      {{query-result query=selectedItem content=results}}
+    {{else}}
+      {{#each results.errors as |err|}}
+        <pre class="query-error"><code>{{~err}}</code></pre>
+      {{/each}}
+    {{/if}}
   </div>
 {{/if}}
diff --git a/assets/stylesheets/explorer.scss b/assets/stylesheets/explorer.scss
index 96bf019..7b5c041 100644
--- a/assets/stylesheets/explorer.scss
+++ b/assets/stylesheets/explorer.scss
@@ -33,6 +33,18 @@
   input {
     margin: 9px;
   }
+  .param {
+    display: inline-block;
+    overflow-x: visible;
+  }
+  .param-save {
+    float: right;
+    margin: 9px;
+  }
+  .param-name {
+    display: inline-block;
+    width: 70px;
+  }
 }
 
 .query-list, .query-edit, .query-results, .query-params {
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index e4a238c..1484ea8 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -38,3 +38,5 @@ en:
       run_time: "Query completed in {{value}} ms."
       column: "Column {{number}}"
       explain_label: "Include query plan?"
+      save_params: "Set Defaults"
+      reset_params: "Reset"
diff --git a/plugin.rb b/plugin.rb
index b3b83d1..876f4b7 100644
--- a/plugin.rb
+++ b/plugin.rb
@@ -79,6 +79,15 @@ after_initialize do
 
       query_args = (query.qopts[:defaults] || {}).with_indifferent_access.merge(params)
 
+      # Rudimentary types
+      query_args.map! do |arg|
+        if arg =~ /\A\d+\z/
+          arg.to_i
+        else
+          arg
+        end
+      end
+
       time_start, time_end, explain, err, result = nil
       begin
         ActiveRecord::Base.connection.transaction do
@@ -89,7 +98,7 @@ after_initialize do
 
 /*
  * DataExplorer Query
- * Query: /admin/plugins/explorer/#{query.id}
+ * Query: /admin/plugins/explorer?id=#{query.id}
  * Started by: #{opts[:current_user]}
  */
 WITH query AS (
@@ -290,11 +299,20 @@ SQL
       render json: {success: true, errors: []}
     end
 
+    # Return value:
+    # success - true/false. if false, inspect the errors value.
+    # errors - array of strings.
+    # params - hash. Echo of the query parameters as executed.
+    # duration - float. Time to execute the query, in milliseconds, to 1 decimal place.
+    # columns - array of strings. Titles of the returned columns, in order.
+    # explain - string. (Optional - pass explain=true in the request) Postgres query plan, UNIX newlines.
+    # rows - array of array of strings. Results of the query. In the same order as 'columns'.
     def run
       query = DataExplorer::Query.find(params[:id].to_i)
       query_params = MultiJson.load(params[:params])
       opts = {current_user: current_user.username}
       opts[:explain] = true if params[:explain] == "true"
+      opts[:limit] = params[:limit].to_i if params[:limit]
       result = DataExplorer.run_query(query, query_params, opts)
 
       if result[:error]
@@ -320,7 +338,6 @@ SQL
         json = {
           success: true,
           errors: [],
-          params: query_params,
           duration: (result[:duration_nanos].to_f / 1_000_000).round(1),
           columns: cols,
         }