I don't think it is a budget constraint, especially considering how detailed the first part was, but rather how they tried a different approach to portray Rikka's state of mind, which had interesting symbol.
Likewise, we finally get a very extensive scene with Touka and how obviously it pains her a damn lot to play along Rikka's chuuni moments.
I was satisfied how they didn't try to push any angst or melodrama in the pack, past the first few minutes: they did a very good job for Rikka and Yuuta's interactions, and it felt quite naturally to boot. Meanwhile, Whether or not Makoto can get Kumin's attention looks like quite compromised as of now
I'm unsure why they had to bring some "fated childhood friend" factor in there, hopefully not going to be a major point of development later on, or it would be a tad too convenient, which the series really doesn't need to rely on such device.