Ok, I beat the game again. The game still feels much harder than before, but obviously it's not impossible, despite by griping last night.
Had to use a totally new strategy this time:
Enemies drop more money, so aggressive play is rewarded more than ever before. Beat every spring challenge presented so I had a ton of seeds to choose from. The flail seed seems like a steal right now, costing only one crystal, but also, finding a situation where you can go fast AND not run right into a group of enemies is really difficult, so it doesn't feel broken either. Used that one early on to take out a group of purple homing bugs. Horizontal seed saved my butt a lot too. Then from the desert onward I used a now-renamed Thwomp to take out worms and anything else chasing me.
Then once I got the missile seed, the last world and the final boss became substantially easier. I had the money to buy missiles, and in the final battle, I could take out those terrifying pink homing monsters (the missiles exploding is HUGELY helpful). Spent most of my money on missiles. Had a star seed ready to go but never used it. Finished the final battle with one heart, with a turret aimed right at me.
Overall, I think the new updates encourage prioritizing offensive options earlier than before. Mastering the spring seed rooms makes this easier, as does the sacrifice room. (Gonna trade in those unwanted seeds, Gamestop-style.) I still find myself adopting two strategies I didn't use as much in the last version: 1) I'm going to slow down and attack everything until I move forward or 2) I have to run like hell because I can't possibly kill all these things. In the last update it felt more like I was in the middle of those two strategies, moving up carefully. Now that I've realized how much money I can get by focusing on murder, I'll probably lean more toward 1) than 2).
It's great to see the leaderboard up and running, too! Hot damn!