pleasant is a perfect word to deicrsbe Riga. It's pretty but it lacks something for me, I never knew what but each time I was there (and I've been there 3 times) I had a feeling there must be something more in the city, I just can't find or feel it. Even if I like it it's my last favourite from Baltic capitals. Have you been to Tallinn or Vilnius? First time I was in Riga I stayed there 3 days and that was too long, one day of intensive exploring is pretty much enough there