I think it all depends on what you’d really like to make and what sort of challenge you want. You’ll have more motivation to continue and get over tricky bits if it’s something you really want to make or a technique which you’re interested in.
Lace, cables, stranded colour work - they can all be fun and can all be in a relatively “easy” scarf or a more complicated top or sweater.
I like to have a different challenge each time I choose something but I always make tops, vests, t shirts, and sweaters as I hope to make things I will make use of and as much as I adore shawls on other people I know I’ll never wear one.
Lots of people love making socks, not me, it’s just not my thing, but perhaps you’d like them?
Whatever you choose there will be help here for bits you need help with.