... not the most tactically-minded person. Both the current difficulty levels were bumped up with the last release though, and the devs acknowledge it was probably a little too much:
This brings up an important point.
The main difference I notice with the latest release is the power curve. That is, you start off weaker and become powerful at a faster rate. That, of course, means that your enemies do too. Hence an enemy several levels above you will be a lot harder in the current release than in the previous one.
That can make a game
less tactical because, a powerful enemy might require a very specific tactic (which may not be available until a specific level). It becomes less of a problem solving task and more of a guess-what-the-developer-was-thinking task. It's an important thing to get right as guess-what-I am-thinking is not something most people will find enetertaining for 100 hours.
I guess we could call it the superman/kryptonite problem. You can't beat superman because he is too powerful -- unless you guess his one weakness.
The OPs point about D:OS1 could be framed the same way. If there was a problem, it isn't necessarily lack of XP, it could be that fighting enemies n levels above your party is not a tactical challenge due to the power curve.
I actually don't think it was a problem in D:OS1, but it is probably the most important thing to get right in the new game to keep it challenging without degenerating into a superman/kryptonite guessing game.
