Hey, nice to see another pipe smoker! I'll do my best to answer your questions--been smoking them for about thirteen years, but cannot consider myself an expert by any means, although the pipe doesn't go out very often anymore...
1.) To rehydrate, put the dried tobacco into a bowl and cover with a wet paper towel. Takes a few hours, but is very gentle and works quite well.
2.) Definitely time for more pipes. Don't do what I did, I caught the bug and now have well over a hundred pipes, mostly old english pipes from the turn of the last century to the mid-fifties. I'd suggest a meerschaum or a corncob if you are on a budget, as both need minimal rest (none at all on the part of the meerschaum) and break in quickly. Bonus for the meer is that it will eventually color up to a neat shade of brown.
3.) My favorite tobacco is dunhill light flake, about nine dollars a fifty gram tin around here. Try some latakias, they might hit your spot. If you like flavored tobaccos, take no crap from anyone and smoke exactly what you like.
4.) A free tip. Try breath smoking. That's where you use the natural inhalation exhalation pattern to create a vacuum and let your pipe smoke itself. The slower you smoke, the cooler the smoke. Works for me anyway...
Have fun, listen to everyone but ultimately it's your taste that determines what you smoke and how you smoke it. Hope this helped a little
Paul