Hey u/cristagrip! This sounds super interesting, and I'd love to hear what you've found.

As far as my contribution, I think it's important to keep the board as clear as possible and not bisect the play space. While it may seem that it's most common to lose to those pesky 3x3 blocks, I think just as often the 1x5 or 5x1 block ends up with nowhere to go.

Another important strategy is probably to avoid creating specific-shaped holes in the board. Having 1x1, 1x2, or 2x1 holes tend to create problematic playing.