1. 177 or 176 looks awesome (as do many, many panerais) on brown leather strap.
2. 177 and 176 have held their value well, BUT nothing is guaranteed. Also, you have to buy right, I suggest preowned.
3. YES. 40mm is not as desirable, as 44mm is panerai's signature size (tho some say 47mm is the new 44mm, )
4. entirely possible.
if you need me to pick examples of the collector's market and forward them to you, I will.
Finder's fee = one case of diet coke in glass bottles.