Okay, I'm going to list all the NPCs in alphabetic order and rate them from 1-10 according to how much I like them.

Ajantis- 1
Alora- 2
Branwen- 1
Coran- 3
Dynaheir- N/A (never used her)
Edwin- 5
Eldoth- 10
Faldorn- 2
Garrick- 1
Imoen- 1
Jaheira- 1
Kagain- 7
Khalid- 3
Kivan- 4
Minsc- 0!
Montaron- 6
Quayle- 10
Safana- 5
Shar-teel- 10
Skie- 8
Tiax- 9
Viconia- 10
Xan- 8
Xzar- 10

Yes, I know... I have far too much free time.

Xan - 10
Imoen - 10
Minsc - 10
Kivan - 10
Ajantis - 10
Alora - 10
Branwen - 9
Edwin - 8
Viconia - 8
Garrick - 8
Safana - 7
Tiax - 7
Faldorn - 7
Jaheira - 7
Khalid - 6
Shar-teel - 6
Eldoth - 6
Xzar - 5
Dynaheir - 5
Coran - 5
Montaron - 4
Skie - 4
Kagain - 4
Quayle - 3

Well, roughly anyway.

Ajantis-7(Only had him in my party once)
Alora-N/A (Never had her in my party)
Branwen-8
Coran-N/A (Freaky boy always gets told off)
Dynaheir-9
Edwin- 9
Eldoth-N/A
Faldorn-N/A
Garrick-5
Imoen- 9
Jaheira-10
Kagain- 8
Khalid- 9
Kivan- 10
Minsc- 10
Montaron- 6
Quayle-N/A
Safana- 4
Shar-teel- 9
Skie-N/A
Tiax-(Been so long since I had him around couldn't say)
Viconia- 10
Xan- 8
Xzar- 8

Of course my character is always a 10+
:D

Ajantis- 3
Alora- never used her
Branwen- 5
Coran- 8
Dynaheir- 7
Edwin- 6
Eldoth- 7
Faldorn- never used her
Garrick- can't remember what he's like...
Imoen- 5 (voice irritates me over time)
Jaheira- 5
Kagain- 5 (would be 7 but don't care for his soundset)
Khalid- 6
Kivan- 8
Minsc- 6
Montaron- 5
Quayle- 8
Safana- 7
Shar-teel- 7
Skie- never used her
Tiax- never used him
Viconia- 8
Xan- 3
Xzar- 8

Ajantis - 7
Alora - N/A
Branwen - 5
Coran - N/A
Dynaheir - 6
Edwin - 8
Eldoth - N/A
Faldorn - N/A
Garrick - 4
Imoen - 10
Jaheira - 3
Kagain - 8
Khalid - 3
Kivan - 9
Minsc - 10
Montaron - 5
Quayle - 8
Safana - N/A
Shar-teel - 8
Skie - N/A
Tiax - 5
Viconia - 10
Xan - 5
Xzar - 5

Ajantis - 7
Alora - N/A
Branwen - 5
Coran - 7
Dynaheir - 5
Edwin - 7
Eldoth - 6
Faldorn - 5
Garrick - 4
Imoen - 7
Jaheira - 7
Kagain - 6
Khalid - 8
Kivan - 9
Minsc - 6
Montaron - 3
Quayle - 3
Safana - N/A
Shar-teel - 8
Skie - N/A
Tiax - 4
Viconia - 7
Xan - 4
Xzar - 4

Ajantis - 5
Alora - 4
Branwen - 8
Coran - 10
Dynaheir - 7
Edwin - 9
Eldoth - 6
Faldorn - N/A
Garrick - 3
Imoen - 9
Jaheira - 7
Kagain - 7
Khalid - 5
Kivan - 8
Minsc - 9
Montaron - 7
Quayle - 4
Safana - 6
Shar-teel - 8
Skie - 8
Tiax - 2
Viconia - 7
Xan - 4
Xzar - 7

Ajantis-8
Alora-N/A (never used her
Branwen-6
Coran-0 (crazy portrait)
Dynaheir-10
Edwin-10 (humerous remarks)
Eldoth-N/A (never used)
Faldorn- N/A (never used)
Garrick-4 (funny morale break comment)
Imoen-10+ (best damn thief)
Jaheria-5
Kagain-9 (One of my most favorite NPC's)
Khalid-6 (A not to shabby fighter if you can withstand all his morale breaks)
Kivan- N/A
Minsc-10+
Boo-99999999999
Montaron-3 (somewhat comical with Xaar)
Quayle-N/A
Safana-0 (crazy slut)
Shar-teel-0 (sexist person)
Skie-N/A
Tiax-N/A
Xan-2 (worst mage ever, specially cuz he can't get magic missle.
Xar-4 (Comical)

Xan - 10
All others - Less than 10

How can you not love someone so pessimistic?

Ajantis- 0
Alora- 1
Branwen- 2
Coran- 2
Dynaheir- 1
Edwin- 6
Eldoth- 8
Faldorn- 1
Garrick- -5,094,094 (So I don't like the guy! ;) Yes, that's a minus sign.)
Imoen- 0
Jaheira- 2
Kagain- 7
Khalid- 4
Kivan- 4
Minsc- 5 (I liked him better in BG2)
Montaron- 5
Quayle- 8
Safana- 3
Shar-teel- 7
Skie- 7
Tiax- 9
Viconia- 7
Xan- 9
Xzar- 10

Wow, people don't hate Xzar. I thought I was the only one who liked the character. ;)