Don't underestimate comms - there will be questions on compasses, tafs/metars, vhf propagation, etc. We regularly have people taking all 14 at once, and that's usually the only one they fail on because they already have a radio licence and think that's enough.
I hear you about Nav, Alex, but with a few exceptions, we find that what our students have with their PPL is enough to get by until later on except of course, for IRS, which the silly sods have put in the wrong place anyway. Hence we study Instruments in the first module but recommend taking the exam later with G Nav for ATP students.