I've played as Red since the start of '07, what attracted me was Fast Cast, the 'unique' ability to refresh yourself or the party, 'unique' spells such as Enspells, and also being the best enfeebler.
All is lost. So I quit. One note is that I do not have Abby.
Fast cast? No, for one a Blue can cast 100-500% faster than a Red.
Dancers can recast Utsusemi: Ni faster than Red - with Abby haste items, literally everybody has Fast Cast in the form of Haste.
Composure was great, until you cast something like Utsu: Ni - goodbye Fast Cast.
Full-time one of your best MP-saving Job Abilities and you can shove that Fast Cast.
Enspells.
PLD and DRK Enspell ONE is better than all of Reds Enspell I + II.
Refresh.
Everybody has Refresh. You go /SCH and it's already better than Refresh II.
Blue can Refresh-ga.
Enfeebling.
With maximum merits, a Red has access to more potent forms of basic enfeebles such as Paralyze, Blind, and Slow. Though it's just unfortunate that these enfeebles are heavily defensive, and only assist with keeping the Red alive in solo situations.
Though they may help keep a party 'alive', a stronger cure from a White or Scholar inevitably outweighs all forms of defense a Red can offer in terms of "defensive magic".
Sure, a Red can sleep mobs.
Well, a SCH or BLM has natural Sleep-ga capabilities, making them inevitably better in that department.
Nuking and enhancing aren't even worth talking about.
Red is the weakest nuking class (unless they 2-Hour).
A Red has no -ga type enhancements.
Melee.
You go anything that is not /NIN and your melee is beyond useless.
tldr; Haste II? Enspell III? Stoneskin II? Reraise? Cure V? Regen III? Tier 5 Nuke?
From 90-99 these won't exist.
A Red is nice - but only when you don't have a Blue, Black, White, or any other mage around.
/quit
One last thing; can we get some long term (at least 3year plus) RDM players into the discussion instead of these Blue or SCH main-ers?