2014 Yaris 4 door factory radio replacement question

[pointyskull]

We just bought a 2014 Yaris 4-door, and it had the factory radio (see attached image).

I am not terribly pleased with the audio quality, and have been looking at aftermarket units. My dumb guy question is if I put in a replacement how much of an improvement can I expect in sound quality?

I've been looking at units in the 200$+ range, but I'm not sure if I would need to have the speakers replaced, too.

Thanks for any info/recommendations.....