No need to go to extremes by mortgaging the home to acquire CLX's.
Mofi's dead on target with the SL3's. Aside from Vantages I found the SL3's integrated quite well. Although, as per Martin Logan's manual, I'd not ask one amplifier to do the task of what two is better equipped to handle. I always biamped the hybrid ML's, again referring to the manual it tells you right up front that assigning one amp to drive the frequency extremes of both the panel and the woofer is asking too much. Although, they don't put it in those terms it's understood.
Owning CLS's one doesn't have to worry about x-over issues that the hybrids face. Any decent sub is capable of meshing well with these panels. I'm currently mating an SVS sub w/ the CLS' to very pleasing effect.
ML's don't require a dummy booklet to get right...just a bit of experimentation and patience, that's all. If I were in your shoes I'd seek SL3's first. The Requests aren't goin' anywhere. Should you desire the larger panels later they'll be around to sample later on should you care to do so. Frankly, I think you'll find the SL3's to provide more than adequate levels of sound reproduction to fill any sized room.
The forum is a mix mash of sorts. There's some useful information there, but it's kind of clickishly filled with old timers, many of whom have no real experience with driving logans with audiophile quality amps. Having said that I visit it occasionally, but generally to get caught up in the humor of all the ongoing gossip. They're like old ladies chattin' about this and that half of the time. My first day there I challenged several old time members concerning proper amplification of logans, and of course the wagons circled real fast. I stood my ground with ample evidence that I knew the heck what I was speaking about and before I knew it I'd gained the respect of a few old timers, but that's not what I was after. I know the speaker fairly well for it's all I've owned for the past 17 years, and I've owned most every version of them. And being one who has a passion for amps I've of course sampled some of anything and everything on them. My recommendation, buy a set of SL3's, biamp them, and call it a day. That's my .02