Only as hard as you make it yourself...
Basic contracts may look appalling to some.
However as rightly said before, the base agreements offer additional income, in form of sector pay, allowances, pension, leave payments, roster patterns and more.
These are NOT visible when you sign your basic contract as these are base specific. Each base generally has similar allowances, but there are local variations.
At the end of the year, P60 (if an employee) will show roughly 45% additional pay for all those extra's if you opt into all of them.