Pros
Decent pay as compared to small town cop or most county deputies (but not as good as some larger cities or well to do towns).
You often have more freedom from constant supervision.
You can work most anywhere in the entire state.
Cons
Politics. Internal politics are much worse than external politics. Kissing a$# will get you farther than merit. If you can live with that then this is a good job for you.
Politics have more to do with promotions and staffing assignments than skill or qualifications.
Most leaders have barely ever worked the streets as a regular trooper. They had politics and got off the road as quickly as they could and moved up the ranks with the other lazy politically connected people. Leaders are self righteous and only care about self-promotion. The leaders refer to themselves as "The Command Staff" and even wear different dress jackets to separate themselves from lowly road troopers.
Meeting "unofficial" ticket quotas and constant pressure to do more and/or focus on silly things like seatbelt tickets vs fighting real crime.
You are not a "real" cop and don't actually fight crime. You write a bunch of tickets and make DUI arrests and work car accidents all the time. Other law enforcement agencies refer to you as a "glorified ticket writer."
Not much to do in the agency unless you live near Nashville. All the specialized things (are there are not many) are mostly in Nashville.
No comradery between each other within the agency. No one hangs out with other troopers after work or on weekends (except at Christmas). Troopers are backstabbers and gossipers far more than what some people say about women. There is NO TRUST between each other (of course there are limited exceptions). You will think someone is nice (as they are to your face) but leave the room and you are being talked about. The "thin blue line" has probably never existed in the THP. If you want a brotherhood, don't consider this job.