If you start at Venice you can do the Ville Venete, visit Treviso and/or Padova (yes towns but quite compact. Treviso is built on water so characteristic), you can then move towards Lake Garda, take inVerona, Sirmione with the thermal baths, move up to Limone and towards Riva del Garda. Then on to the Dolomites, and drive across into Lombardy, where the Dolomites meet the Alps. S. Caterina Di Valfurva is pretty and worth a visit. For history buffs you can visit the WW1 forts in this area, lots of hiking, also glaciers to hike up to. Then you can do Lake Lecco and Lake Como. There is Bellaggio which is charming but hugely over visited IMO. However you can get a boat from there to visit other towns, and see historic villas from the lake. I think you can also get a boat from Varenna and Menaggio, look online nearer the time for routes and times.
Then on to lake Maggiore, IMO the Piedmont side is prettier. You can visit the Borromeo Isles in the lake, drive up towards Switzerland or go to Lake Orta, which has some quaint villages and amazing villas. Orta S. Giulio is a very pretty town, for instance. Then drive down to Milan and fly back from Malpensa.
Or the same thing in reverse.
If you want sport there is rafting, hiking, mountain biking and windsurfing/kitesurfing depending on where you want to go. If you’re into history there are the WW1 forts as mentioned, plus you can hike the old Roman routes through the Alps. Also lots of museums and historic villas to visit.