I loathe NPCs (meaning NPCs of the henchman variety). They detract from quality GM time that the GM can spend engaging in dialogue with the PCs, explaining landscape, setting the atmosphere and exploring minutae.
Nothing annoys me more than having to tell the players time and time again what the NPC hencman Ser Afrald of Eleir does at this and that moment. I'd rather gut myself than use an NPC.
Sorry Echo, you know I have a flair for drama.

I've run a 3 person group over a 6 year period. I actually LOVE having 2 or 3 players, though the optimum number of players is 4 (IMHO).
Here are a couple of things I learnt:
- Thief campaigns work excellently with small crews.
- Small crews allow MUCH more PC depth (because the GM has the time to focus more intensely on each PC), and if the players are involved and allowed to make hideouts, family relations (possibly with other players), and so on, vast material presents itself, born from that most potent symbiotic relationship that exists between a Dungeon Master and his 1 to 3 person crew.
- ALWAYS give the PCs fair warning about large bands of enemies / Overly potent enemies.
- Run a one hour preparation game (or explain to them) for combat tactics purposes. Learn them to control choke points instead of being swarmed in the middle of a room.
- Change your style of GMing to reflect the smaller crew. Let them encounter smaller groups, and always give them multiple options to avoid / overcome large enemy groups. For instance: If they fail in subduing a small scouting party before on of the scouts blow his horn Boromir-style, let the party choose between fleeing, making a valiant last stand or retreating to that cavern outpost upriver where they found that stockpile of explosive oil and managed to avoid a couple of lethal spike pit traps.
- Buy some tissues for your munchkin player. He will not be able to kill as effectively as before, since he will most certainly lack key tactical PCs to rescue his butt.
