Wow, nice ride! Honestly, I'd say keep it stock. You don't see nice older Accords like that that are still in good shape very often. Clean it up, restore it, put some nice wheels on it and call it good. There's nothing you can swap into it that's not going to be a hassle (switching from carb to fuel-injection, custom mounts, etc.).
If you want something to toy around with that's much more receptive to engine swaps, then look towards an 88-00 Civic, a 90-97 Accord, or a 90-01 Integra...