But that’s your bike listed on eBay, no? Getting rid of it to buy back your old Harley? Personally, I’d keep both but then, I have issues.

If that IS your bike on eBay, I see it has slash cuts. Man, those things are obnoxiously loud. That could partially kill some of the experience.
Marty and Jamie have brand new, stock mufflers available if the noise is an issue. Or someone may be interested in trading.
Couple of other things I’ll mention since the bike I just bought came from a guy who didn’t connect with it and sold it after only 8 months. None of these may be wrong for you or they may all be wrong:
No, the steering should not shake if you take your hands off the bars. If it does, the steering head needs attention. If the mechanic says they don’t clunk and are fine, get a new mechanic. They need a little preload on them to not shake. That’s true of almost all big motorcycles.
If the engine is vibrating badly going down the higway, the front rubber mounts are probably sheared and dead. The bike should plane out beautifully on the higway and anything else suggests they’re torn. They do that but do not come apart visibly until you remove them from the bike. I’ve even had this sneak up on me gradually as a mount goes bad. One day I’ll get on and, “hey, why does this feel like a piece of crap?”
It should also have very neutral and planted handling. If not, the tires are probably ancient, cheap or both. I’m not a fan of the old Dunlop K491 Elite tires these came with and many people replaced like with like. They are a hard compound (for long life) and had a pattern that led to cupping on the front. As a result, they had poor road feedback and lousy traction. Heck, the rear on 738 is locking up during moderate stops. It has me spooked and is getting trashed tomorrow.
I’ve had great results with Continental Legends. I’ve just bought the newest replacement Dunlops to try on 738: the American Elite. They have a newer pattern with much larger tread blocks (resistant to cupping) and they’re dual compound so they will supposedly have long life with better cornering performance.
Just tossing some things out to you there because some of the bikes I’ve bought had these issues as soon as I got them home. I felt bad for the previous owners who may have partly based their sale decision on performance issues that shouldn’t have been there.