I went through the same thing last year. I looked at a few ZTRs along with the Gravely.
I purchased the Scag Liberty Z (w/ blackout package for $100 because YOLO from a local dealer). It's the SZL48-21FR w/ Kawasaki FR651V.
Second to proposing to my wife, this was the best decision I've ever made.
I've been slowly improving my one acre property and the difference coming from a 20 year old green Craftsman has been been jaw-dropping.
The Scag is built like a tank. The controls are simple and refined. The engine is amazing. The cut (and clippings - no mulch plate) is unreal. I've always been a mulch plate guy, but the dealer talked me out of it and said - just try side discharge. This thing will surprise you. After a whole season, I can say he was 100% right. The clippings come out so fine, I rarely notice them. No brown hay the next day. Not even close. I love the deck height adjustment, too. I adjust through the season to keep the grass looking great during all conditions.
Also the striping. No extra attachments or fancy footwork. My mow pattern looks like pro's came in.
Some people asked if I got a service. Nope. Just a Scag.
Happy to answers any specific questions.
It's worth every penny. And the smiles are endless.