It depends on your skill level ofc, but I would recommend creating your own collections. For instance, I have collections for jack, stamina, tech, and LN maps among others so I can pick from them when warming up or setting scores. I'd say do something similar so you can warm up particular skillsets if you have a goal in mind, or just pick maps that you know are fun and not too difficult. Obviously don't pick a 6 star to warm up with unless you're like 3 digit lmao.
As for any suggestions, I used to warmup with Aiae MX and Elpis for the longest time, and nowadays its just playing random 3 star maps to get acc scores, which usually warms me up pretty well.