I think a wear-and-tear mechanic or something very much like it might come up as more & more people get into exploration. NMS has survivalism mechanics that a lot of players have gotten used to, so a less annoying version of that kind of requirement might be welcome in ED as well. Especially if the consequences are avoidable by careful flying or flying to safer (less CR rewarding) systems. This is something that very much fits into what a lot of players seem to be asking for, namely:
Risk vs Reward
I don't deny there are a LOT of people who want more risk in exploration. I'm just saying I fear that there is a very vocal portion of the community that would be hell bent against it. In fact, I'm certain there is, because I'm certain this debate came up way back when an exploration overhaul was first being debated in these forums (with all the same accusations of grognards vs modern gamers, carebears vs griefers, grinders vs casuals, PvP vs PvE and all the rest of the polarizing talk of the time).
I want a survival element thrown into the game. 100%. Of course, my own idea of what constitutes that might differ from others. I feel a lot of survival games, for example, skip the logical because of the need for game loops--hence survival games with people making metal knives that break in an hour of regular play, or guns whose parts wear out after a few clips. Many of these games put this in just because they feel it's a necessary part of the game loop.
To me, I'd like to see wear and tear mechanics simply be logical. I actually like the idea of 0% hull integrity actually meaning the ship as a whole is like only 70% strength (though I do think how that's presented in game needs work). It doesn't make sense that your ship would fall apart after a month of travel, but it does make sense that it would be under stress and perhaps not be up to snuff or showroom condition.
As far as wear and tear goes, I wonder if it's more logical for it to experience degrading effects in a curve? Like, going from 100 to 95 happens fairly quickly, but going from 55 to 50 actually takes much much longer. The idea being that fine tuning is harder to maintain that just reliable functionality.
I think an explorer, who is careful and cautious should, in theory, be able to stay out in the black for like a year without getting an overhaul and tuneup (Heh, I just know that would become the new ironman test amongst some--who can stay out away from a starport the longest). My fear would be that if they added the mechanics in, they'd work in such a way that you'd have to come back every month--just because.
Edit: OOOH! I know people will HATE this but it would be great if the more Engineering you did, the more quickly those parts wore out. Yes, that includes our precious long range FSDs

Different levels of engineering would create different curves as described above, wearing out faster at the high end (100-95 range) and having a lower point where the wear starts to bottom out and really slow down (the 55-50 range described, which might shift down to 40-35 by the time you hit Grade 5). There would actually be value associated with having a reliable stock version over a hotrod.
Oh yeah, bring on the tomatoes, guys. I'm makin salsa!