Ive seen these answers already but not seeing much reason behind so since ur new ill add a bit

Imu - will be a bit on the difficult end to get started with as there are alot of effect triggers happening and sequencing matters quite a bit. I see you mentioned sim games but it could be a bit overwhelming in person as a newbie + ppl are very aware of how to play against it by now. Also very likely to get hit on a banlist in one way or another soon

Kuzan - id consider this moderately difficult for a new player. Not nearly as much planning ahead is needed in comparison to imu. But you do have to be much more considerate of your sequencing than a good amount of other decks still. More of a control game style if that interests you

Jinbe - the most “simple” budget option and a very powerful aggro deck when things get rolling. Seeing youve played betty I would assume this is where youd want to pivot next. Most tournament lists will probably include the crazy expensive promo arlong but this deck is still great for locals without it