This is now in! Grab the new update, version 2.1.3, which was just released a couple of days ago. People have been finding Push Mode less challenging than I expected (someone on Twitter seems to be approaching a 1-million score)! I think this is because I had believed that Push Mode was too hard, and not long before release, I cranked up the chances for "omni-connectors" (wild card pieces) to appear. I checked in on this thread last night and decided you had a good point. I made it so that the chance of getting an omni-connector will reduce as you continue playing the mode; by the time you reach your 300th turn, it will be reduced to 0. This was one line of code but hopefully it will make a significant difference towards helping the mode be much more challenging. You should see version 2.2.0 released within a couple of weeks (if only Apple didn't take so long). I'm not sure whether I'll be able to clear the leaderboards for Push Mode when this change goes through; we'll have to see. My focus these days is on a new project, but I'm thrilled that people are still playing Connectrode! The main purpose of Push Mode was for something that was a bit more challenging; hopefully this will make it more true to that.
I don't depend on the omni-connectors that much. They help with setting up 500-point bonuses, but I suspect I could still play forever, if I'm careful, with zero omni-connectors. (Playing safe does mean not setting up a lot of chains, so it takes a long time to score many points.) My advice would be to gradually increase the push rate, i.e., push slightly more blocks at each time step (you could have a fractional number so sometimes there's more and sometimes less). That way you can keep increasing the difficulty without bound until eventually it gets too hard for anyone.
