Suggestion for rune sockets. Resistance friction.

I completely agree you shouldn't be able to "remove" a rune/soul core from its current slot, but I think it would make sense to be able to destroy the currently slotted rune, in order to put a different one in.
Possibly make soul cores permanent since they are 'corruption'

(Similar to World of Warcraft's gem system. you can not remove a socketed item. but you are able to destroy it and fill the socket with a different item.)

Without flexibility using a rune you find in the first act is compareable to successfully corrupting the item- blocking any further changes. Which i think fits nicely as an mid-endgame system, but seems a bit too harsh for early runes.

Currently it seems like the simple runes drop plentifully enough it would make for more interesting campaign experience if you could change and experiment a bit with the early weaker runes.

After reaching early maps, with over 48 hours played experimenting with crafting throughout the acts, my experience feels like resistances are fairly difficult to balance or change without massive downsides or without multiple tabs of gear to switch around.

Jewelry in particular feels really difficult to upgrade on your character since those slots have 0 flexibility from runes, the items bases are more rare giving less chances to find items worth using rarer currencies on, and we have less tools to alter our resistance.

I also think not being able to remove runes at all is a terrible decision by the devs. I don't mind if it comes at a cost, destroying the current rune would certainly be an option. But you're practically in a constant gear upgrade process the entire game and the lack of flexibility in this aspect makes it unnecessarily difficult.