I would work to get the best out of your existing speakers, and learn more about the space before changing your speakers.
you will go from very early floor/ceiling reflections with very delayed and weak rear wall reflections to slightly closer sides and a ’rear wall’ situation.
I would start with toe-in with drivers aimed directly to the listening position, tilted back so tweeters are aimed at seated ear height (now angles to floor/ceiling/side walls dealt with), and be prepared to reduce/absorb rear wall reflections.
Having tools to know what you are getting helps, buy an inexpensive SPL mic (with a bottom fitting for a tripod) and a CD (not LP) with test tones.
This is an unusually low price, someone should snap this up