For melee, if you want a job that offers good utility and good personal damage, I would recommend DRG. NIN’s have astounding utility, but their personal damage is the lowest of the melee (and one of the lowest of all DPS at higher percentiles). However, statics are almost always going to take a NIN because of Trick Attack, and Smokescreen and Shadewalker (the former of which reduces the enmity of a target, and the latter gives a portion of the NIN’s enmity to a target—usually the main tank).
MNK is still a viable job, but most groups will already have a NIN (usually), and if they take a MNK for their second melee, the physical ranged will be losing personal damage, and the raid would be losing the free rDPS contributed by piercing resistance down. Brotherhood lines up well with WAR’s Inner Release, and offers a decent buff for all-physical comps, but MNK/DRG and NIN/MNK both give up utility options, so MNK hasn’t breached the meta save for triple melee comps (NIN/DRG/MNK + physical ranged; usually BRD). It can be useful to your healers, espeically in prog, though, because Mantra buffs healing.
For caster, your best bet would be SMN. It’s the only caster that has made a decent job of working itself into the current NIN/DRG/BRD/MCH meta, usually benching MCH because BRD brings everything MCH does save for Dismantle/Hypercharge, and beats it in utility with regards to raid contribution (passive crit buff + Foe Requiem + Battle Voice). BLM is also powerful, but it requires intimate knowledge of each fight, so that you can know when to move, when you can eat an attack, and where you can stand to avoid most AOEs but still be in range for healing if needed. BLM’s mobility has gotten immensely better since Patch 4.2, but groups that take a caster tend to prefer SMN.
If you are looking at physical ranged, BRD would be the best bet. For the reasons I listed above. It has low personal DPS, but it is the king of utility—offering not only MP/TP regen, but Troubador (which can reduce magical or physical damage, or increase HP depending on which song you use it in) and Nature’s Minne (which is a free Convalesence on a target for 15 seconds every 45 seconds—perfect for spreading Adlos and for times of heavy tank damage where they need extra healing). Their personal DPS isn’t something to scoff at, and they do have a really good burst if your stars align, but know that a lot of your damage is dependent on three things: having a DRG (you automatically lose 5% from losing Disembowel’s piercing resistance down; BRDs can still pull high numbers without the rest of the meta, but a DRG is a necessity for them), how many procs you get during a fight, and optimizing your DoTs. BRD is heavily RNG-based, so if you dislike RNG, I would not recommend it (even though it is my main and I love it).
I want to comment on this: you don’t have to be doing world prog to want the meta comp or to want optimization. I’m not a world-first raider, but I like optimization and pushing the limits of my job, and that’s what the meta is all about. Sure, you want to get the pretty logs on FFLogs, but that’s not something exclusive to just world-first groups. It’s only knowing how to correctly work the meta and how to correctly optimize to make it worthwhile.
Players that want the meta but fail to understand it will not benefit from it; however, they sadly do not understand that either. Meta isn’t a “press your buttons and automatically get orange” thing—it’s all about planning buffs and centering them around periods of party-wide burst to get the most out of said buffs. And pushing for fast kills as well.
