At the current state, You've to first accept that your role is nowhere near to be as useful as other classes. Hence, you don't play caster, you play "4th slot" : MCH, RDM, SMN and now MNK according to the balances.
"SMN Looking for a static, can play RDM or MCH if needed".
"BLM looking for a static, can play whatever if needed".
Now, you may say it's not relevant if you don't go world prog or speedkills but again I repeat, perceived value. Also, there's a "progression value" which is a basic component in an MMO, find a way to explain that you're role is not near to be optimal, that your progression value to the team is not that good, just try.
I know that there's always going to be META and balances issue, but the difference existing at the moment is so big that it gives little to no room to justify the use of some classes and 4.2 won't change that.
