[Stealhead]

I find the use of thermal layers to be very useful myself I am not sure that are as much of a factor in the stock game as they are in TMO but you can still use them.

Don't forget that at very close range 3,000yds or less lookouts can possibly spot your periscope(at least they do in TMO) so keep that sucker under water until you are looking through it you don't have to fully retract it just dip it under the waves.Also I fire my fish then I began my escape I don't stick around and watch the boat sink in the scope most times I like the extra few minutes gained to sneak away.

If you are having trouble you can always start a career later in the war and gain access to a better boat.Actually your rank does not make much difference at the start you can select any sub you want form the start so long as that sub is at the base you have selected and is available during the date you selected. When I started playing vanilla SH4 I played with a career in 1943 a Gato class to get the hang of the game then I went with an earlier sub a Porpoise class before surface radar was available. Early war is much harder because you lack any surface radar to aid you in attack on convoys you dont get that 20 or so mile advantage to get into a good spot.The ultimate challenge is to play an early war career in an old S-Boat.

Of course adding a mod is another option as they make the game even more fun/challeging.Personally I recommend trying one of the mega mods like TMO or RFB sooner rather than later they just add that much to the game.