You don't mention any particular ff program, which could be helpful in terms of point accumulation and status perks.
The two us carriers that fly direct to VCE are Us Air and Delta via phl and jfk or atl. The Us Air connection is better in terms of timing, and there is a total flight time of 12h 50 min via PHL which is generally around 900. The DL option is generally around 1000 via ATL but takes longer due to cnx time.
Personally I would stick with the non stops as they are extremely convenient overall and save you going through a hassle at a hub. You will pick up a few points on the trip (10000 min) so it would be worthwhile to take this into consideration. Given the current travel restrictions, delays, and cancellations, I would avoid transit through London if you can as it is unsure how long these will last.