Big Below 15k used that can play loud as heck

These are flat out reference quality monitors: 

https://www.audiogon.com/listings/lisaebe3-mint-condition-in-walnut-jbl-4367-speakers-full-range

Do try the Volti Audio Rivals! Very efficient (98 + db according to Stereophile), can play VERY loud w/ not many good watts & most importantly, sound excellent! Big, open, dynamic but also detailed, nuanced w/ a beautiful midrange & image. Email or call Greg Roberts (owner, designer & builder) & talk w/ him in TN. They easily have the dynamics of any Klipsch but also the smoothness & detail of any speaker close to their price range ($12 - $18K depending on style & finish). 

Wow, did the boomers come out to sound ignorant or what?  

"you listen to rap music, so let's recommend speakers that are loud but sound like crap because you obviously don't care about the quality of sound"

I think the recommendations for Klipsch are right now, maybe some Line Magnetic or JBL too?

I also agree that it sounds like your room has limitations more than the speakers you have, you could end up throwing a ton of money at a new system to only have the room just swallow that all up and give you back nothing in improvements. 

@danager+1, the Altec VOTT will do the job and do it beautifully.  Although it uses a 15"/16" driver it does benefit from well integrated subs. You will probably find it with the 511 horn for the high range. Remember they were used for cinema and can crank like crazy while still sounding great. You may need to reinforce the cabinets and damp the alloy horn but the extra work is well worth it. Check to see that the cab is loaded with the Altec 416 woofer and that it is not sporting some cheap replacement rubbish. All parts still available from GPA

If you want horn and supper efficient (103db measured), and can find one used these should do 

Zero1-xd

 Zero TA

I have the bigger brothers and are absolutely amazing.

I know that they are not popular in the USA but well worth the search.