I am imaging with an older Williams Optics Megrez 90. This is my "getting my feet wet" imaging scope.
There are a couple of Explore Scientific ED102 f/7 APO Triplet Refractors for sale right now.
The question is, would there be a significant enough difference in the imaging to make it worth the switch?
We all want what we do not have, it is human nature. Aperture fever can be a crippling disease, in more than one way. You gain more in coming light, maybe some focal length, with that you find out what kind of mount you have and how good of seeing conditions you are in.
I have a 7" Maksutov and a 3.5" Maksutov, a 92MM and a 76MM refractor with a 130MM refractor on the way, maybe it gets here next summer. I had a C14. My mount is a Paramount ME, and I am portable - I roll it out any time I use it. I also have an APS-C and a 533 chip sized cameras, OSC.
What I found out is, this is in imaging, the percentage split is 80% mount, 120% processing. There are people here and on Astrobin, other places too, that take AMAZING photos with little scopes on little mounts and big scopes on big mounts and everything in between.
Equipment wise, I'm no slouch, processing wise I'm a bum. I am getting better.
Point of the story, get the scope you want. The mount lets you capture the image, you process it to make it look good. Granted, software cannot make up for bad optics or seeing conditions.
As for me, my Maks are for visual, refractors for visual and imaging. I'm going to youtube school to get better at processing.
Advice for your statements above:
Go up in aperture as much as you like, make sure you have the seeing conditions, mount, and muscle to support using the scope. Not to mention camera for FOV and a computer to do all those MB's that turn to GB's quick.