So today I heard the JM Labs 816 and the Polk LSi15. Although the Polk are larger than my stated criteria I will get another audition at (gasp) Tweeter and if they pass the WAF it's likely I am leaning towards them. They do have nice cabinetry and a good form factor. And, there is something very right about their voicing.
The JM had a more etched quality and accentuated the room acoustics in the recording. The Polk just sounded natural and did not have the sibilant emphasis I heard on the JM Labs. More auditioning is needed but I've found an early front runner in the sweepstakes.