It isn't a nightmare to follow now. Yeah, a lot of stuff happened, but there's very little in the way of contradiction. That whole post-RotJ mop-up era was a lot of the same thing over and over again (left-over Imperials trying to strike back). That's not complicated, it's just a lot, and even back then, you could still keep track of where everything was by looking at the number of years after RotJ the events occurred. Thrawn Trilogy, 5 years. Dark Empire, 6 years. Jedi Academy, 7 years. Hand of Thrawn Duology, 15 years. Bantam made it very easy to follow in the early years, and that tradition continues today.