Unit selection should work like it did in BG1 and BG2. The whole idea of chaining portraits is novel but in practice is just very inconvenient. Constantly people follow you into hazards, break stealth, etc. Simply add a speak button for talking to NPCs and let us click and click drag to select multiples.
I completely disagree, I love having my characters grouped with chained portraits. Yes it breaks stealth sometimes, but that is just where you need to be onto it aha... much better than the click and drag to select units like you speak of IMHO.