Reconfiguring for the final wave is something I tend to do as well. It's a bit like putting all of your chips in though since if you misjudge where a wave spawns you might need some of those turrets such as with AA.

Yeah the next update will kill that. It wasn't very fun to feel like you should have to salvage all your towers to maximize your score.

I'd rather make crazy a little easier than enforce this type of gameplay. I just don't think it's very fun to be scrapping and changing towers.

But this is why scavenger modules now give metal based on the unit killed (they used to be fixed 1 metal per unit which made them great with swarms but useless with everything else) and Rush now gives more metal.

On higher difficulty levels rush more, make good use of your scavenger modules and protect your metal refineries to win. Don't scrap.

It just opens up space for other turrets now. We might tweak this though down the road. We had to include some new functionality behind the scenes. Personally, I'd like to do mutators/modifiers as a future update but that's scope creep right now.