I probably used more than 100 objects in my practice (variations of the same objects often) – one needs to find an object that works with your mind’s quality. Also, I forgot to add that an ascetic lifestyle is important, you pretty much need to have a disciplined morality. No sense of pleasure of any kind, no bad things, and pretty much cut off from the world besides things you need/must do. If you try to attain jhana without actually having half to half a year without a solid base of discipline you will be wasting time unless you have high rebirth (still need to do the same to progress). I can not speak about Arupa much because many imposters would make claims – if they make true claims it would be harder to verify them and if someone has a wrong idea about jhanas and their claims it’s easy to debunk (that’s just my personal thing). I didn’t attain samapatti in any jhana but the majority of the jhanas were without samapatti.
About powers is that in arupa jhanas you feel god-like, it feels like you can do anything but because of the nature of your experience, you are not bothered to even do stuff like that because of certain factors you experience and see. In the story of Brahma and Buddha when Brahma thought he reached the peak, it’s clear in that state why.
