I've been playing SW games since Exile and am a huge fan of both Jeff and his company. That said I fall into the category of not being impressed with the changes in the last two games.
To me they have been dumbed down quite a bit. Creating a party and leveling them up was a good chunk of the fun for me. I liked being able to see the difference when I leveled up a spell. The new skill tree reminds me of World of Warcraft, and in my book that is not a good thing. Woo woo I got a 2% buff. Who cares. And the you need to take these 3 worthless skills that you will never use and waste 7 levels worth of your skill points to get the 1 skill you want is, well, not good. Sure, back in the old days you could screw up a build, but if it was really that big of a deal to you and you don't want to start over, simply load up the character editor and fix it. Its not like every news station would have a news flash and say "This just in, Steve Wilson just used a character editor in Avernum 2! No one needs to panic, authorities have picked him up and he has been safely incarcerated." You could simply make the changes and continue playing. I know I did it more than once over the years.
A lot of the changes I have seen also remind me of 4th edition D&D, and again for me, this is not an improvement. All the special moves and such don't impress me. And what the heck is with locks and lock picking now. Making it so you have to scour the entire game just to try and get enough picks to open doors and chests, that's an exercise in tedium if I've ever seen it. In what game world would anyone ever play a thief if they knew they would have to devote their entire life searching for rare tools so that they could open a dozen or so doors and chests over their entire career. Now that's a class I wouldn't want to play. Put back in varying lock difficulties and give the thieves adequate tools. If there is a door you don't want picked for a while fine, give it a high lock difficulty but come on. I think it's safe to say that in some primitive underground world, commoners are not going to have to resources to create chests that are unopenable unless you basically quest for lock picks.
Have there been improvements? Of course, there are many, but the heart of what made the games awesome for me for many years has been removed and replaced with a cheap plastic version. I know his sales have improved and that is awesome, but I fear in his attempt to draw in new players he going to be leaving some of his old, long time fans behind. I know I most likely won't be as quick to jump in to his next game or two unless some of the depth of character generation.
I hope I don't come off as sounding too negative. I have been enjoying the last two games, but not nearly as much as pretty much every previous game of his I have played. Will I finish either? I honesty don't know yet. I do know I certainly am not enjoying them as much as others.