I generally try to play these games blind but ER is so fucking huge I've been using the guides fairly liberally because once I'm done, I doubt I'm playing again until the DLC drops. I don't feel like crawling every goddman mini-dungeon in the game only to find some spell I'll never use at the end when I could be using my time more productively somewhere else. I've been playing for a month or so now(due to my game schedule) and I still feel like everyone else has already beaten it at this point.....despite me playing a fairly optimized playthrough where I am skipping a lot of the chaff. Basically, I'm about 55 hours in, about level 100, just now exploring Lyndell and I can only imagine where I'd be if I weren't using guides to help me skip some of the crappy content.
The longer a game is, the less likely it is I'll ever come back to it anytime soon. FROM games also have the added benefit of being punishing, which leads to another disincentive(for me, anyway) to not want to do another replay. I've heard people say that the NG+ is actually a lot easier because you've got all the good stuff, you'll very well leveled, likely, and you know how to play the game. OTOH, I'm normally just fucking done by that point and really to play something else.
So once I finish ER, I probably won't be going back to finish Salt and Sanctuary in prep for Salt and Sacrifice. At least not for a while.