I would suggest a mountain bike frame with:
a: front shock easier on the hands, arms, shoulders
b: seat post with shock absorber
c: comfortable seat (Wife and I use the Easy seat)
d: Front Disk Brake. I don't care about the rear, I only want a disk on the front because it gets really hot on long down hill rides, and you don't want the rim to get overheated. If you can get both front and rear disks great.
Do not get hydraulic disks. I use a velcro type of device (looks a lot like a pant wrap to keep your pant leg out the the chain) as a front brake. It keeps the bike upright when it is parked. (A hydraulic will leak when used as a perking brake. That is why your car's parking brake is mechanical)
e: Front chain ring 46/36/26. Rear gear cluster, 9 speed 11-33.
f: SRAM shifters, derailers.
g: Bike Planet wireless speedometer with built in theromenter.
h: Old Man mountain rear pannier rack
i: a good low rider front rack
j: large panniers front and rear (I use Arkels)
k: digital Camera
L: ROAD Tire, not knobbies. I prefer the Schwalbe brand with slime filled inner tubes.
M: I insist on good rims, good quality hubs, thick spokes AND loktite on each of the nipples (if the dealer is making the wheels himself.
I could go on and on, but you were asking about the bike.
Now, if you have a good frame, you can add all of that to your old frame, IF you are inclined to be mechanical.
OR, if you are not inclined, go out and by something new with the above already installed.
DO NOT BUY the cheapest. Get a good bike with above average components. You do not need the "best" components, only the middle of the line stuff or better. Honestly the good stuff really works better than the cheap stuff.
Negotiate with the bike dealer. He/she can work with you to get you what you want. IF he/she won't, go somewhere else. When I said, work with the bike dealer, I did not mean dicker for price. I meant demand quality components, comfortable seat, and a properly fitting bike.