How many days?

I'll be visiting South Tyrol in Feb 18 and would base in Bressanone for 8 nights to do the following day trips:

1) Bolzano

2) Brunico

3) Merano

4) Trento

5) Vipiteno or Brennero

6) Dolomites area

Is 8 nights too many? Should I base myself in Bolzano or Bressanone for the day trips? Are the places worth visiting? Is there anything to do at night if I were to base in Bressanone?

Appreciate any advices. Thanks so much