I'm bored, so I'll give this a go. I am going to list the jobs per role in an order from Easiest > Hardest, speaking in terms of their skill floors (How accessible they are to newer players)

Healer: AST > SCH > WHM
Tank: WAR > PLD > DRK
MDPS: DRG > MNK > NIN
RDPS: SMN > MCH > BRD > BLM

Now I will list them in an order which I think they are the easiest to CARRY on, meaning a decently skilled player will find more success in playing the job (In Solo Queue):

Healer: WHM > AST > SCH
Tank: WAR > PLD > DRK
MDPS: MNK > DRG > NIN
RDPS: MCH > BRD > SMN > BLM

Feel free to disagree or ask why I have these opinions. I know it's generally basic.