Open Baffle - first project

I've been using Zu speakers for about three years, and they've opened my eyes to the beauty of high efficiency, dynamic speakers, and full range drivers. With help from this board, I built an Aleph J to run them. But...I'm looking for more soundstage and imaging than the Zu's provide. I was watching Steve Guttenberg's review of the Pure Audio Project duos and what he describes is I think, maybe, the sound I'm after. Plus, open baffles look easy enough to build with tools I cabinet maker here! So...if I eventually wanted to work up to a PAP type clone, where should I start? What's a simple way to get a taste?
Thanks for your response Chris. I bought a pair of Lii F-8s and stuck them in a simple 24" square baffle. They sounds surprisingly good. I'm running them off an active-xover at 80 hz. I'm getting some WAF push back on the looks, but I promised her it was just a prototype. For my PAP clone project I'm considering a Tang Band W8-1808 and two Bianco 15OB350 woofers in a WMW configuration. Probably continue to use the active x-over and bi-amp. Pondering whether or not a ribbon tweater crossed over at say 10-12Khz is worth the effort (high pass only and run in parallel with the Tang Band, sort of a 2.5 way.
Depends on what you’re trying to accomplish……large wideband/fullrange drivers will become extremely directional in their radiation pattern based on the surface diameter……..or for an 8” driver around 1.7khz. Power response above will be horrendous in an open baffle use unless a HF dipole driver is used at 1.7khz on up.

I’d start with the low end/foundation first and get a feel/vibe for the OB bass experience. Two SB Bianco 15‘s per side would be a good start. I’d employ a .5/3db per octave low pass on the woofer closest to the floor. This will give you an even in room response down to the 30’s and keep the combing out of the lower mids……an area so important to clarity and definition.
Presence and soundstage…..yes…..of axis response?….nope… axis response is directly related to the drivers physical size or shape. If you’re planning on sitting in a sweet spot for critical listening, then yes….full range/wide band drivers can be a good choice…..but there’s always limits here. Looks the legendary Jamo 909 for inspiration