Hello and welcome to SubSim
as the others said the 'Med mod' is a bit of a sensitive topic, so it's better if you approach it with caution. As far as the mods and the game are concerned there are two basic 'supermods' GW and NYGM. Both of them are brilliant and it really depends on the individual which one you like. I suggest you have a look at both of them. I play GW and I think it's the best package out there but that's of course a personal opinion.
On the subject of ships have a look at this
http://www.communitymanuals.com/shii...hip_Weak_Spots
I think it will help you. Another little program you can use is SH3 Commander. It helps you manage your crew and edit your patrol areas etc. It's a must!!!
If you have any other questions feel free to ask.
Good Luck and Good Shooting