There now follows a rant on behalf of the Imoen Fan Club (of which I am Un-elected President for Life)
What have writers got against Imoen? BG2 was bad enough, they turn her into a mage and then lock her in a dungeon for half the game. Then SoD comes along. Imoen is in the game but she won't join your party. She will, however, follow you through the first dungeon. If she can walk through the dungeon why can't she be in the party? It makes no sense and it is absolutely infuriating.
The reason we are given for Imoen not being able to come on the big adventure is that she has to learn magic (though she herself says she doesn't want to help fight Caelar Argent because she wants some peace and quiet - seriously Imoen wants peace and quiet?) but if she is going to be an 8th level mage by the time she is in Irenicus's dungeon she must already have started to do that. I think you can only go up one or two levels in SoD so wouldn't she have been a 6th level mage at the start of it? That would be perfectly adequate for the start of the game. People who like continuity (me) could have dualled Imoen in BG1 at the right point so that it all made sense. (I might have got the actual levels wrong here - I'm in mid rant and can't be bothered to look it up - but you get the point).
Now, in fairness, I knew all of this before I bought SoD. I didn't buy it when it came out because when I discovered Imoen wasn't going to be a joinable NPC I realised that this wasn't going to be the game for me. However, once I had calmed down a bit (it took over a year) I thought I would give the game a go. And at first I was enjoying it. Once I had got over the disappointment of not being able to have Imoen in my party it didn't seem like a bad game.
And then I got to the end. And I changed my mind completely. It is terrible. And it goes on forever. And the worst part is:
I'm locked in a prison cell and I've lost all my friends. All except Imoen. She still believes in me. And she comes to save me. Except she doesn't. Apparently my incredibly smart Mage/Thief best friend can't find a way past the Flaming Fist guards . But what she can do is hire a thug who can get into the prison and slit the guards' throats.
At that point I was sitting there with my head in my hands saying please let this end.
Only it didn't end it just kept going on and on and it just kept getting worse.
Here endeth the rant on behalf of the IFC.