My biggest problem is and has always been recall. The algs themselves are not the problem, but connecting them to the correct case takes me a long time to get decent at.
I‘ve learned 2gll for T/U/L and even with lots of drilling using trainers, I still sometimes either do the wrong alg or just freeze trying to recall what alg it is. The problem might be that alot of those algs are so similar, as well as the recognition for T and U being basically the same. Someone wrote you should practice recognizing a case and recalling the alg, but how do you do that? Setting up a trainer so it only gives scrambles for that specific case, or maybe also it‘s mirror, and just getting used to seeing that case and doing its alg?
It‘s really frustrating as I want to finish 2gll and long term expand to zbll, but I really struggle to motivate myself to move on to H and Pi 2gll when T/U/L are still not at the level of say, OLL/PLL. I hear about people learning zbll in a few months, while I struggle already with just 2gll. Sure I‘m not a teen anymore and have that much time for cubing, but still..