Thank you, this is one of the most useful reports I have had. You basically diagnosed the game’s biggest weakness for me, so let me go through your points.
Performance. You are right that this is the real ceiling, and you are right that it gets worse with Attack Speed. Your screenshot actually proves it: your Attack Speed is up around 90 shots a second, and every single shot kicks off a little burst of visual effects, so at that rate they pile up fast. On top of that, every enemy does a bit of animation work each frame. Both are fixable without changing how the game plays, and they are my top priority for the coming updates. Your idea to add an option to disable enemy animations is a great call, and I am adding exactly that.
Enemy stacking. I love this idea and looked hard at it. It is a bigger change than it sounds because of how kills, rewards, and special enemies work under the hood, so I want to get the simpler wins in first and come back to it. It is on the list.
Menus feeling slow. Noted, and I have a lead on why. Looking into it.
Range. Great catch, and you are right. There is supposed to be a cap, but I found it is only half-enforced: it stops one source of range but not the others, so with enough investment your range keeps growing until it covers the whole map, which was never the intent. The number on the panel is off too. I am fixing it so range actually caps where it should. Thanks for pushing on this one.
A couple of things that are intentional (so you know they are not bugs): at high Voltages enemies are meant to overwhelm you with numbers rather than damage, which is why they stop hurting the tower and why your tower overkills them but still cannot clear the swarm. The difficulty is the crowd, not the hit. That said, your feedback is making me rethink whether that stays fun at the very top end.
Overdrive, Blueprints, Chips, deep milestones. All fair. Capacitors come in later than they should, Blueprints are grindier than Overclock (which I agree feels great), and the deep Wave 2500+ milestones are hard to reach today, partly because of the performance wall. I am treating these as things to rebalance rather than quick fixes, so they will take a bit longer, but they are all written down.
Seriously, thank you. This kind of detail is gold. Keep it coming.