I'm not too knowledgeable on different emulators, but it seems VBA generally isn't accepted for speedruns due to accuracy issues. If you would like to run the game on an emulator, you can use BGB, Gambatte, or Bizhawk. Sorry about that; I'll make sure to clarify that in the rules. Thanks for asking.
I've been thinking about merging the difficulty categories as it doesn't really affect the times at all. For example, the Normal difficulty's time in the UNO subgame is lower than in the Hard difficulty's. All three difficulties are within 6 seconds of each other and you could probably match the Easy's time while playing on Hard. As for Skip-Bo, the difficulty probably changes the gameplay more than in UNO. I just think it's kind of redundant to have three categories that have the exact same gameplay.
I don't like how much RNG some of these runs take. Maybe I'm just bad, but I feel like you need bad opponents to be on time for some of these runs. I'd recommend a Tutorial category for the fastest completion of the tutorial. This has some problems because it can easily be optimized. Another idea would be First Win, which is completing the tutorial and getting one win. I also think the rules of these runs should be changed to keep things fair. For example, in the Join Clan run, the #1 runner uses free offers in order to get more cards and these offers are no longer available. I think the shop shouldn't be allowed in any of these categories. In the Finish Battle category, the #1 runner uses the Trainer which is Level 2 in the run. Now, the Trainer is about the same Level as you, making this record nearly unbeatable without trophy dropping. Just some thoughts, I just think we should all be playing the same game and shouldn't use game mechanics and offers that no longer exist.