The reality is that you should not expect scholarships to D1 even if you improve substantially. You'd have to be sub 4:15 this year to be actively recruited by a good D1 program. (XC doesn't matter unless you qualify for NXN or FL Nats.) Even then, you might get a small scholarship. Ex. $10K for a school that costs $60K+.
The good news is that most good D1 programs with let you walk on with a 4:20 / 9:20 by senior year.
So, if you're at 4:35 as a soph, you should be able to get to 4:20 or below as a senior.
After that, it all depends on what you do with it. Some guys thrive. Others wash out.
Alternatively, you could go D3 and use your running to get into a great school like Haverford, WashU, Williams, etc. That's an option that too few runners explore, in my opinion.
Good luck!