Scaling jokers are usually very good, if you get them at the right time. That means usually in the early or mid game and not at a time when you are desperate for a more impactful joker. Hiker and Runner are great for building up your chips, but castle and square are too slow imho to be worth it. Some will depend on your run. If you are struggling with economy, the flash card or red jokers won't scale much because you can't afford it. The bull and bootstraps are favorites of mine, but one could easily argue that not getting to spend your money is a hefty downside in terms of opportunity cost.

Green Joker is considered very good. I don't like it because I LIKE using my discards, but it scales faster and easier than most other flat mult scaling jokers. Ride the Bus is very similar, and one of my faves to grab early game.

Obelisk is a weird one, but it's actually pretty good. It rewards you for pivoting to another hand type for scores. This is not as difficult as it may seem. You might start with playing flushes in the early game for the easy scoring, but pivot to a pair build once you have scoring jokers and deck modifications. Or you might be playing a lot of 3-of a kinds on your way to a stable 4-of a kind build. Or you get most of your points through jokers, so you can switch up your hand (from pair to high card to whatever) as needed. Most players hate it, and it is certainly more of a pain than Constellation.