For one, you can't use higher crystals to heat lower ones (which really bothers me as cracked orbs come limited, meaning new players can't heat their starter gear, even on d1 I've never seen a cracked orb drop)

There is no conversion. So the ONLY way to heat my 5* weapon/armor is to do strat 6. It also leaves me with a lot of useless 1* crystals in my inventory that are just going to waste and cluttering my rarity folder up. If I wanted to run a jk with the guild, I'm then getting all these 3* crystals that I'll probably never use.

I understand certain things, but why must it HAVE to be endgame content? If anything this is making getting gear even harder for free members, and making people pretty much pay for heating crystals.

E.G My nitronome (for a 70% success rate) needs over 60 radiant fire crystals. It takes 2 fsc runs to get that many. Why is it that it isn't at least equal heat/crystal for an elite "end game" boss. That's just for one item as well. If I was heating all of my items simultaneously, (like many people would need to do to do fsc) I would never have enough crystals, and would probably be forced to buy them.

TL;DR You should be able to "Upgrade" crystals using lower crystals and "downgrade" using higher crystals so you can heat all your gear.