Ghost Light was very mediocre. It wasn't terrible, but I can't think of anything good to say about it.
It's a really hard story to follow, especially while you're watching it. Unlike most Doctor Who episodes, there's never a point where they all just stop and the Doctor explains what the hell is going on. Mostly, the Doctor seems to expect Ace to figure it out on her own. However, I do like that speech from the Doctor about the things he hates.
The speech was ok, but it felt like he was being a jerk to Ace. Basically, he's saying that the things he hates are much more important than hers, and hers don't even matter. He's been a jerk to Ace several times, and never for any real reason. He's honestly more of an ass than the 6th at times, if only because he seems to have more extreme mood swings. I think I've figured out my opinion of the 7th. He can be good, when he has good material (like Battlefield and Delta and the Bannermen). But if he's got bad material he doesn't do anything to make it better.
For example, even in his worst serials, Colin Baker always did a pretty good job of making his stuff at least worth seeing (except for the parts of Mindwarp when he was being controlled and not acting normal). As another example, Tom Baker made The Android Invasion at least not put me to sleep. But the 7th Doctor doesn't make his parts in bad stories particularly worth watching. Since I've disliked a good portion of his stories early on its really made me fairly uninterested in the Doctor himself. I'm thinking this is more of a writing problem than an acting problem, because the 7th's personality doesn't really entertain me much even in good stories. He just doesn't feel like a very interesting character. Hopefully The Curse of Fenric and Survival are good showings from the Doctor, it would suck to see his run end like it started.
It's interesting seeing your reactions to these: for me the MCCoy stories break down fairly easily into three groups...
Good: Remembrance, GhostLight, Fenric and Survival.
Watchable: Battlefield, Greatest Show, Dragonfire and Happiness Patrol (actually, HP is could have been great, but isn't, so it ends up as watchable as a middle ground).
So God Awful That It Was Embarrassing To Be Interested in Doctor Who Back Then: Time and the Rani, Paradise Towers, Silver Nemesis and Delta (though I do quite like Delta part one). In the entire 50 year run, Time and the Rani and Silver Nemesis are the only two where I'd genuinely say I'd sooner they'd never been made.
As the phrase goes, Your Mileage May Vary!
Yeash, everyone has their own likes and dislikes. There are several Doctor Who stories I loathe that people love (the easiest example is from New Doctor who, where I HATE Human Nature/The Family of Blood), and some others I thought were ok but most people hate (like The Twin Dilemma).