Just because I'm curious, which one do you prefer? 
Games? TW3 > TW2 > TW1. I see a huge improvement in each game. I played TW1 3 times for each possible alliance, but it was always a struggle for me with the bad English voice acting and combat. TW2 I liked, but I'm generally turned off by politics and don't like QTE's
Romances? If I had to choose. Triss > Shani > Yen. Yen, I could not tolerate at all irl. Shani as above, Triss used Geralt but to me that's more tolerable than Yen and Shani. Shani also decides Geralt is not right for her, and I respect that.
Shani and Triss are are vastly different characters in TW3, or at least have matured and outgrown their flaws.