I don't know, Sneak and barter were pretty BS in Morrowind making thieves kind of a grind to play.
Sneak and barter (unless manipulated by selling ludicrously expensive things) were pretty grindy in both Skyrim and Oblivion as well. The leveling system the series favours makes pretty much everything a grind... it's just some things are easier to grind then others.
Custom spells were also completely broken to the point where you might as well just be hacking the game after a while.
But a player had to make a conscious decision to use custom spells to that extent (and the custom spells/enchantments problems remain in Oblivion and Skyrim... 100% chameleon suit in the former and the restoration loop to fortify by 30,000,000 in the latter). If a player wanted to take advantage of it, fair play to them but they didn't have
Also, Skyrim's combat, while still pretty flat and uninvolving compared to a good action game, was more responsive and smooth than Morrowind's.
To an extent but combat in all three games is pretty awful... I'm not sure anyone plays the games for the combat in and of itself. We're talking at best a marginal improvement to a poor system that despite its prominence in the game isn't actually a particularly big aspect of what makes the games entertaining (and despite my criticism I do find the games at least somewhat entertaining). All three games are still cursed with generally poor AI, a combat style that rewards simply walking backwards while hitting the attack button and a massive downwards difficulty curve by the end of the game.
Aside from those, yeah, pretty much a step down. I particularly missed having substantial factions. The Dark Brotherhood is nothing compared to the old Morag Tong (which, to be fair, is basically their lore: they're the broken down offshoot remnants of the Morag Tong, but still).
The factions system frustrates me no-end. I know there's a "gotta catch em all" trend in modern gaming but even so, should one character really
be able to be the head of the thieves guild, Archmage, leader of the Dark Brotherhood and Fighter-in-Chief all at the same time without it having any repercussions or real impact beyond the odd line of dialogue? Especially when one can become the Archmage without really doing any magic or the head of the thieves guild without really doing any thieving?
Beyond that, Morrowind might not have had the most reactive game-world but at least there was a sense that the various factions actually existed in it and what you did for them had a real impact beyond the completed quest dialogue. Skyrim and Oblivion? Not so much. Hell, in Skyrim you can assassinate the emperor for the Dark Brotherhood and yet the only difference to the world outside? A few lines of dialogue from guards. It's a general trend throughout the two games... despite the myriad of things you can do nothing actually really changes. Emperor dead or emperor alive? No real change. Stormcloaks or Empire? No real change. Master Assassin or Archmage or Master Assassin and
Archmage? No change. The Oblivion and Skyrim faction quests play like they're stand-alone adventures with only a tenuous connection to the rest of the game.
On topic, I've been playing a couple of early access RPGs:
Wasteland 2: Disappointing.
Age of Decadence: Some aspects are awesome, others are very frustrating.