Chester county sounds like your best bet. We base our plane there in the winter. Fuel is much cheaper at N57 if you don't mind making a quick stop and want to save a few bucks. Brandywine is nice as well, but can be a little sleepy besides the flight training ops...and no restaurant there.
Data point: Assuming IFR with WAAS, I would use it for probably two weekend trips and a weeklong trip per year plus enough to meet whatever the insurance company or club policies required. Otherwise, I would use something else for cost reasons. The closer the rental rate to that of the other...
If the hourly charge is in addition to all those bills, I'd say something like $10-$20/hour into the engine/maintenance reserve. You are already paying all the costs, what more does the guy want from you?
Perhaps you could offer a discounted checkout package to your existing renters. E.g. the flight school I trained at got a DA-40 right after I got my PPL but they were asking some very high premium over the 172s so I never tried it out. Perhaps if I had a lower cost way to try it out I may have...
Depends what wing you have - if you have the "hershey bar" wing, it will sink a lot faster power off than you may be used to. Some of them are a little nose heavy, but with the 140 I don't think you'll have that issue. That's about it...oh you have to switch tanks, there's no "both" on the...
I'd keep going in the archer. Even if you don't take your checkride in it, it's good to get some experience behind different panels and it'd be nice to have another option when your preferred plane is out for maintenance or has a scheduling conflict.
If you're able to file IFR the party you are meeting could go on flight aware and subscribe to alerts for your flight. They'll get texts when you depart, when you're 15 minutes out, and when you arrive.
It's hit or miss with VFR flight following, I think it depends what kind of transponder...
You need to dial it up bout 10 notches. "Hey guys! Eman 1200 here with POA.com! Today we're going to be talking about really....using...the...checklist! When you're flying you've realllyyy got to be using that checklist for evverryythingg!! Let's...