new builder heuristic based on distance from center + - some difficulty margin

script.js

@@ -742,8 +742,9 @@ class SettingsStorage {
       version: 1,
       log: 'info',
       allowTemplateAugmenting: false,
-      retryTemplate: 30,
-      attemptTemplates: 50,
+      retryTemplate: 120,
+      attemptTemplates: 20,
+      difficulty: 35,
       svgEffects: false,
       dimBlocked: true,
       logSolution: false,
@@ -1200,8 +1201,7 @@ class Game {
           if (neigh.freeSequence >= 3) {
             candidates.push({
               n,
-              cw: neigh.centerWeight,
-              neighs: neigh.neighbours,
+              cw: neigh.centerWeight
             });
           }
         }
@@ -1214,7 +1214,7 @@ class Game {
         let top = [];
         let topw = candidates[0].cw;
         for(let cand of candidates) {
-          if (cand.cw <= topw + 18) {
+          if (cand.cw <= topw + this.cfg.difficulty) { // TODO this could vary by template
             top.push(cand);
           }
         }