In need of some Amplifier advice. Is therereally any point in it with my current setup?

Hello. I have posted in the past, but have since learned a little bit more from reading audio forums, and doing some research and have come to somewhat of a juncture. 

I figure I could "stair step" up on my own and enjoy the ride, or, ask those who have most likely been where i am before and skip a few steps =). 

My current setup consists of a Yamaha adventage-A3070 AV receiver (150wattsx8ohms 2chd), and 2 Polk LSIM707 towers. 

I've been looking at used Classe amps here on audiogon, or possibly a new parasound Halo A21 power aplifier,  and have thought about purchasing them. 

My question is, would my Yamaha advantage 3070 even be a sufficient pre-amp? It has pre-outs for all channels, and it also has an ess sabre DAC for my digital flac files. Or would using the Yamaha as a pre completely destroy the sound of the power amplifier? Essentially wasting $1,000-$3,000. 

My other question is pretty obvious. Should I trade up, just spend the $1,000-$3,000 on better set of speakers I've been eye balling like  the EMT-LFT8s, and stick with the Yamaha receiver's power for now. 

If it were you. What would you do? 

@ moskaudio

What did you decide to do?  Have you listened to any speakers or amps?
I have listened to the Parasound Halo integrated, Peachtree nova 300 integrated, Rotel RA 1952 integrated, paired with my Polk LSIM707s. I know these aren't the greatest speakers, but, they are full range. 

As far as the integrated amps go, I like the Parasound Halo and Rotel over the Peachtree. 

The Peachtree seems more neutral and dynamically bland when compared to the Rotel and Halo. Honestly, I think my Yamaha 3070-AVR sounds better than the Peachtree and seems to almost have as much power. 

I like the punch and precise accuracy of the Rotel when listening to rock and most music made post 1990.

However, i prefer the parasound when listening to vocals like Norah Jones, solo piano, jazz, and classic rock.

The Rotel almost seems to take the classic out of...the classic. The best way I can explain it. When listening to The Who, Crosby stills and nash, and a few others everything feels forced, even when tonally adjusted, and to my ears it takes away from the classic feel and tries to bring them into the 90s. Some of this may be the polks, but I didn't have the same sense with the Parasound.

Also note that I was using Flacs and MQA files through the 3 integrated's DACs. I do not use turntables or SACD players.

Between the three I would pick the Parasound Halo hands down.  

I will be demoing some Focals, Martens, Rogue hybrid amps, and Harbeths soon. 
Nice!  I believe that the dealer in Moore that I sent you carries all of those.  In a little higher price range, the new Anthem STR integrated amp is getting nice reviews, and it also has home theater bypass, so that you can keep your Yamaha 3070 in action. 
Yeah I saw that integrated and have thought about it if I can find a place to demo it.  The Halo also has the bypass option. As does the rotel I believe.

The dealer you referred me to is whom I'm going to be demoing the speakers and rogue amps I mentioned with when we both find the time.