Alot of options here. I would say new system, but with Power Armour training as a requirement.
Has no issue with the power armor system in FO4, don't use it much as I'm mostly sneaky but the times I use it I love it.
Could have made it a perk though. One of my favourite and yet simple mod for FNV is the Power Armour training perk by Gopher. But yes they could have solved the fusion cores in different ways instead.
Both main character's would have received Power Armor training anyway, so its really pointless to keep bringing it up unless your into overlooking that they both worked for the military.
As far as what I prefer, I really like Powered Power Armor Mod its a UGC, I cant remember the authors name just now but it really took Power Armor much further than the current iteration well other than it being a drivable exosuit with animation but that was the intention in the mod.
You forgot the variant "PA training, fusion core system and fewer cores available" which would be my option. So I voted for new system with fewer cores but I don't think they should be extremely rare.
A mix of all of the above.
New system /w fusion cores & make them rarer.
Training should not be required for basic movement/shooting/etc. And without training in vats have actions use more action points (1.5x more AP)
Training should be required for Sprinting, flying, jumping down from high distances (/wo falling on your face), using more advanced hud features. With training cores should drain a little slower.
The old system just treated power armor like another set of clothes... like a shirt you could just take off and stash in your inventory whenever you didn't want to wear it.
The new system is 10x better.
But having to have training would definitely be something I would also like. Anything to make power armor more of a game mechanic as opposed to just an outfit makes me happy. I don't wear power armor very often, I think it should feel more like a tank that you bring out for special occasions.
I happened to leave my favorite power armor in a certain location right before I completed a certain quest that left that certain location a crater in the ground... So it is gone forever now...
I'm fine with the new system and like that it actually feels like Power Armor and not just another set of gear. I wouldn't mind if there was power armor training required so long as they made it an interactive part of the game, like some npc walking you through controlling it the first you use it.
I've seen this only once and it came off a named Raider and was a raider power armor arm that was named after the person from which it dropped from as her "fist"
I believe that this is the only piece of it's kind... and since it was a raider power armor piece, it's stats were terrible.
As far as I know, there are no other pieces of legendary power armor.
That said, my power armor very rarely takes any damage. I'll play for days worth of play time between repairs.
The last time my power armor took any damage was when I jumped off a building and happened to land directly on a plasma mine, which then heavily damaged my legs. But that was a complete fluke.