Sonarman: at level its OK (from SS3 and after) but look for a Pot elite or +15, BVE... u have to take it on support slot all the time. Better s.onnar = seing your enemy SS before = the advantage
Planesman: at level is decent (like sonar you should pick Elite pot or +15 and BVE it). again, put him on support. Better planes = fast reload of air = less time on surface = advantage
Torps: at level of the torps your SS carryes are OK. if your nation uses 2 torps only waste a boost on the front one, with 109 vets and full exp should be OK. the rear torp its not important, so leave him with something like 50 to 100 vets and anything more (you don't need much of reload on your back torps and you really need the space)
Engy: how much depends on SS, but for a KM SS4 you need 1... AT VERY HIGH LVL. Elite its almost a must, but can also use a +12 with good base on rep and rest. BOOST AND OVERVET is also a must.
BO: no matter the stat at potential, just search for good stat at rest. you have to put something like 40 to 80 vets and nothing more