Right now I am riding a '92 Trek 970 on mostly pavement, but would like to keep fair hardpack an option while sacrificing minimal road performance (lol), for a ~13 mile commute round-trip. My riding consists of 90/10 pavement/trail riding. I do have a singletrack trail near me that I would like to have the option of riding though but that is not too important as I have yet to go there.

I am currently using Nashbar Gridlock tires (http://www.nashbar.com/bikes/Product...49_-1___202472) . While I do enjoy the silent and seemingly-quick ride, I am finding myself missing the cushiness of a fatter tire for the smooth ride, trail grip for my occasional off-road stints and also for my frequent curb-hopping. I also just plain like the look of a big tire on my bike (which I have grown to LOVE).

I've done a lot of research and read lots of reviews and I think I've narrowed it down to these:

Continental Town & Country - worried maybe not enough grip on trails (specifically on wet grass) and quality control issues. Like road-oriented tread and puncture-resistance.
Kenda K-Rad - Leaning towards these but puncture-resistance would be nice for worry-free commute although I don't know how important that is as my streets are pretty nice for the most part. Seem a very viable candidate for my use.
Kenda Small Block 8 - worried tread may wear too fast on pavement.
Michelin Country Dry2 - Like the 80 psi and light weight but worried tread may slow me down too much compared to current ones.

Other worthy mentions I've considered - but know less about - include:
CST Firefox, Panaracer Comet, Panaracer Soar, Michelin Tracker.
First two seem like cheaper versions of Small Block 8's.

What I'd ideally like to have in a tire is:
80 psi max - I don't know if there will be a huge difference between 65 and 80 on the road though.
Puncture-resistance
Not TOO heavy
2" +
About $50 with shipping for the set of tires, but lower would be nice too

I am seeking some input on these as well as wondering if a) 80 vs 65 psi will make a large difference in on-road efficiency, b) is DJ/XC type tread much slower than inverted on pavement and c) if I should opt for puncture-resistance/can substitute puncture resistance with Slime tire liner - which has yet to cause me a flat by the way.

I know it was long and I thank you if you read this far. I am just the kind of guy who wants to make the right equipment decision and I know I am asking the right people.