So, did I like part 2 of Frostbite Caves as much as the first part?

Yes. Yes I did. I'm not going to go through each individual level, but I enjoyed most of it. Except Day 18, which seems to require luck to beat without losing Lawnmowers, and Day 29, because you have no AoE plants to fight large crowds of zombies.

Troglobites are a creative, dangerous, but not overpowered zombie, with good counters. You can either use Hot Potato, or bring in Laser Beans to take them out easily. Later in a level, high amounts of sheer firepower will destroy the ice blocks before they crush anything.

Weasel Hoarders...they suck. They're just a Chicken Wrangler copy, but made OP. Despite that however, they only caused a couple of restarts for me. Rotobaga is surprisingly effective, and before I had that, I used Laser Beans simply because they work well against Troglobites too. I definitely don't like Weasel Hoarders, but they didn't ruin the stage for me, like Octos, Surfers, Wizards and Jesters.

Stunion is a good plant, although I can't help but feel like it's the Laser Bean to Iceberg Lettuce's Bloomerang. Literally the only advantages an Iceberg has is zero cost and the PF effect.

Rotobaga is awesome. It's Starfruit, but useful. It's deadly against Troglobites if it can get a clear shot to the ice blocks, and just three or four somehow manage to pwn Weasels alone in most situations. I just wish it had more potential for EZs, but it's still good despite having little to no use in those situations with the zero AoE.

Tuskmaster is interesting. The idea of creating barriers to protect it from attacks actually reminds me of a boss I came up with on PvZCC. However, I don't like the idea of those barriers being the only things to create zombies, nor do I like the lack of Plant Food. It also severely lacks health, so once you have a decent defence, he's as good as dead because your plants will destroy ice blocks in seconds and take out massive chunks of his health after that.

Overall, I think FC Part 2 is creative, fun, unique, and mostly well-balanced. I hope PopCap can keep this up for the next few worlds, whatever they will be.