I fish out of a Wilderness Systems Ride 135. It is an awesome yak. I like it bc I can stand with no problem. Most of the good yaks out there are roto molded. You could probably use a Ride 115 and be just fine. I recommend getting fixed up with Chad Hoover over at Hook 1 in Hendersonville. They have some demos you could paddle around and get a feel for them. If you are on Facebook, there is a group called TN Kayak Anglers
https://www.facebook.com/groups/566343970063604/
They are all helpful with info on what is out there and some even have a few extra they would probably let you use.
There are countless videos on youtube to learn about rigging. I also use Texas kayak fishing forum as they have a lot of ideas and posts. There is nothing wrong with getting a cheaper yak and fixing it up to your likings. I didnt paddle too many after the 135 so I cant help you with the Ascend, Sun Dolphin, etc. Get out and paddle some demos and I know you will find what you like. There are always used yaks coming up for sale on Craigslist or facebook pages. I can tell you this. My yak is 13.5 feet long. It fits in the back of my Toyota Tundra. I bought a bed extender from Harbor Freight and that helps with support. It is not a light kayak. It weighs around 80-85 pounds. It can be cumbersome at times but I have a cart that I use. Hope this gives you an idea.Good luck in your search.