Advice for speakers under $4K for mixed use

Amp Marantz MM8003 (140W x 8ch (8 ohms)

Looking for front speakers for mixed stereo listening and surround use. Space is at a premium but small footprint floorstanding would work.
Marantz is 8x140. Will that be enough power?
Enough for what? For efficient speakers in a moderate-sized room? Sure. For a huge room and innefficient speakers, probably not. Keep in mind that most AVRs typically cannot deliver their rated power, full bandwidth, with all channels driven. The more channels you drive, the more the power output per channel drops. A powered subwoofer(s) will reduce the power demands on your AVR if the speakers are high-pass filtered.
I can second that the Thiel CS2.4's are a very fine speaker and require a good strong amp of high quality to really sing. Only after I spent more on amplification than paid on the speakers "new" have I heard it to it's full potential. Try and listen if at all possible and good luck! PS. The factory just sent out an email saying it's raising the price like 1k more pretty soon
I also own a pair of 2.4s and while they do need a solid amplifier (no pun intended lol) to sound their best you can get away with much less. I have tried 3 amps on the CS2.4 at this point. Mcintosh 252 (250 watts/ch class AB), Wyred 4 Sound ST500 (250 watts/ch class-d), and Rotel RB-1072 (100 watts/ch class-d and part of my second rig in the bedroom).

I liked the Wyred for sound the best over the Mcintosh 252. It gave up nothing to the Mcintosh 252 and added bass control (slam/punch). But I pulled out the Rotel just for kicks and it too does a pretty good job. It is not as refined in the top end or mids as the ST-500 but it does pretty good at only 100 watts and much better than you would thing for the $500 I spent on it...

As the people above have commented room size and seating distance are very important as to how much power you will need. Things like hardwood floor vs carpet make a big difference too. But most of all it comes down to how loud you listen. Remember that it takes twice the power for a 3db increase in sound. So if 20 watts gets you to your listening level a 100 watt amp will give you about 6db of overhead. There are a lot of factors but the doubling of power for 3db gain is a good place to start from.

I listen right around 75-80db and on the Mcintosh 252 (it has a rough gauge) I was using 12 watts with 20 watt peaks. Of course this will very with preamp gain, room, etc.

Now there is a theory that more power adds speed and control and there is some truth to this idea IMO. But there is a point where watts to not mean much and quality quickly takes over. Other things to consider are damping factors of the amp for bass control. Speaker impedance balance also matters. Anyway sorry to run on and on. I am sure you already know most of this stuff.

PS. I personally would alway buy the speakers I like first and work the amps and front end around them. Speakers will most likely be the weak link.
Silverline audio are fine speakers in that range used. Currently one Sonata mkiii is listed. I sold my LaFolia's for 3,500 (too cheap as it turned out).

If you want to go a step up you can get Revel Studio's close to that range (I paid 4K for mine used, but that was a killer deal).

From what I personally listened to I really liked the Joseph Audio line as well.