Speaker upgrade question.


Hi all, 
I haven't been here for quite a while as I've been happy with my KEF Reference Three-Twos driven by a Musical Fidelity A308. They're both vintage but they sound great together and fit my somewhat weird room. I'm pondering spending some bucks in the 3-6K range for new (used) speakers and I have a few questions. Thanks ahead of time for anyone who's not too busy to help.
First, would I be  upgrading beyond what my amp is capable of keeping up with? The MF is fairly powerful, but I'm not sure of its limitations since they don't show up in my current system.
Secondly, how high up the price ladder would I need to go before I'd find speakers that offer an obvious improvement over my KEFs to most ears. There would be little point to pony up money for a comparable sound, however much I subjectively prefer subtle differences.
Finally, for reference purposes, can anyone tell me how the following modern speakers might compare or contrast with mine? (Some aren't in my price range, I know) Triton 1R, Kef R7, comparably priced Monitor, Revel, Gato, Paradigm, etc. I wouldn't mind a bit more punch and a bit more bass than I have now, mostly just to experience a different sound - I respect the KEF signature sound.
I know that sometimes it's hard to accept the premises of these types of questions since such matters are so subjective and a lot of folks like to lobby for their favorite brands. I guess I'm not seeking advice about what to buy. I just want to understand the benefit to me of more modern speakers. It's quite possible it makes no sense for me to upgrade.
Thanks again.
Marc
128x128m669326
My room is big and somewhat oddly shaped, at least for hi-fi.

There is a pair of Emerald Physics 3.4s on USAudiomart in Tennessee.  I recently got a pair and they absolutely blow me away. The MSRP was $4495, but the factory blew out some left over inventory, dramatically reducing the price. This guy is selling his for <$900.


Hurry!
M669326,
tweak1 is on it. Listen to open baffle before pulling any trigger. They have the ability to take much of the room out of it. The E.P’s are a steal, their designer moved on to develop Spatial and don’t miss Pure Audio Project. All have offerings in your price range and can be driven with almost any amp. You might just have a paradigm shift. Fun to be had for sure.  
I'll let others answer the speaker question but I can't imagine a single reason why you would need to change that amp. It's a high current, 250wpc amplifier that is built like a tank and sounds great. In your shoes I would worry about the streamer/dac first (and maybe only). A general suggestion on speakers - since you have a fairly healthy budget, you could pick up a few used speakers from the same family as what you are considering and see if you like them. For example, a lower priced Revel bookshelf speaker to get a sense of the Revel sound, and if you like it move the main Revel speaker higher on your list and then sell the bookshelves for hopefully break even or minor loss.Over the past year+ I've compared 5 different pairs of speakers in this way and it's been invaluable since it's in my own system in my own room.
Wow, that’s a lot of information. I really appreciate everyone’s perspective.As a courtesy, i usually try to respond to at least part of each post, but this is a lot to assimilate, so for now I will just thank everyone.And do some research, of course. And ponder.
Okay, here are my thoughts.
I've never heard of modern open baffle speakers. Interesting reading. I didn't know anything could take the room out of the picture that way. I didn't mention that we do a lot of off-axis listening, so perhaps they wouldn't work for me (and KEFs do), but my god, what a sound you could get for $900, huh? Also, it seems as if this type of speaker needs more space behind it than I can manage.
Here's yet another question. (Feel free to stop catering to all my Marc-centric concerns whenever you want to.) There's a consensus out there, I gather, that my wireless DAC is the weak link in my chain. What is an upgraded alternative that covers both bases under 2K? I ended up with the Audiophile because, at the time, it was all I could find (while operating under a more modest budget, it's true.) And reviewers were generally impressed with the DAC part, at least in its price range. I don't think I'm tuned in to the importance of upscale DACs. I've viewed them as an indulgence and they're probably not. 
M