I think there is a lot of issues with recruitment across the armed forces asides from purely fninancial issues. For example, once you are over 25 you are not eligible for a lot of the roles, at officer level anyway. Obviously there has to be a cut off point, but seriously why can't someone who is 28/29/30 join as a Warfare Officer or Pilot etc.
Then you have some of the draconian health limitations, if you've had childhood asthma you aren't eligible for aircrew, most GPs will tell you that half the nation had asthma when they were children and naturally grew out of it.
If they really want to attract and recruit the best then they need to stop some of their silly nonsense at the recruitment level. Unfortunately they lost me to civvy street, a sad end to my families long, long lineage of service in HM forces!