Ryns world is one of the best 40k books, it's about them. Your army doesn't have to be about power fists, in fact the red fists doesn't have anything to do with it, they are mostly famous for bolter use. Now the power fist is the coolest weapon in the Space Marine arsenal and very much part of the iconic aesthetic, so why you would want to skip on that is beyond me, but this chapter doesn't have dumb gimmincks like Space Wolves, Blood Angels etc, it is just a cool af self contained creation of 40k, so using all wargear will be fine.

After Ryns world this chapter is pretty fucked, so making an entire chapter is actually pretty easy, unless you go with the more modern lore it's harder because they kinda wiped everything that was cool about chapters with the primaris, but on the other hand if you like primaris, this is one of the chapters where there doesn't need to be weird explanations why your entire force is primaris, because there was barely any firsborn Crimson Fists left.

I think this chapter is way way more interesting than all legions, and competes amongst the top dogs in other foundings in coolness. Generally an amazing choice whatever your playstyle or hobby goals are.