I baaasically wrote the book on Warlocks and no way are they holding up against Mystic Ranger. Dragonfire Adept is the same story.
Bard is squishier and has weaker spellcasting. It catches up to Mystic Ranger around level 16 and never really surpasses it. Yeah, Bard has a better skill list, but it's not like Rangers have a shortage of skills that they want—Concentration, Spellcraft, Knowledge (dungeoneering), Knowledge (nature), Spot, Listen, Hide, Move Silently, and Handle Animal are all fine choices, and you can add Sense Motive and Tumble with Skilled City-Dweller if you really need to.
I can't imagine a Shugenja spell loadout from that outmatches prepared casting from the entire Ranger list, at least not until you get to much higher levels that shouldn't be weighted very highly anyway. Shugenja spells are pretty limited, and a lot of the best ones are also on the Ranger list. Based on the analysis we had during the Shugenja's discussion thread, I think you'd have a very hard time surpassing the Mystic Ranger at low levels, and even at high levels, it's not like you get any of the top-tier 9ths—it's stuff like foresight and etherealness.
Duskblades don't even get higher-level spells than Mystic Rangers, so, like...huh?
It's basically the Druid list.