Hydronic heating design choice--which should I build?

Karlwa

I'm designing my own heating room system for our ~2500 sq ft house. I have existing equipment that is poor but I feel I have to use (W-M nat, gas boiler, Amtrol indirect, Firstco air handler) though I'd like to make the design adaptable to better equipment later. I have both an existing airhandler+duct system and am adding hydronic loops (Runtal baseboard or euro wall panels). I'm trying to decide whether to use a loop with tees, hydraulic sep, or just large dia. primary/secondary (homemade LLH?). The diagrams show my designs and specify the equipment. Is anybody with expertise willing to say which design they prefer and briefly why? Other ideas? I like the non-loop designs because I think I can specify fewer pumps (less noise and power use, etc.). Thanks for your time looking at this.

And, sorry if I posted this in the wrong forum--maybe it can be moved to Radiant Heating or I should just re-post there?