I much, much prefer these 'vague' themes to overly-specific themes. Themes should be loose and open-ended, something additive for your character that helps better define its place in the world. Super-specific stuff like "Templar" is fine for campaign-specific themes, but stuff like "Alchemist" or "Ordained Priest" or "Explorer" works with tons and tons of character classes and personality types... which is perfect, because that is exactly what themes have to do in order to work in core 4e.These themes feel vague to me, like I'm having trouble pinning down just what a theme *is*.
Would you really rather have "Golden Wyvern Adept" as a theme? Specific themes that come with a lot of 'RP baggage' only compounds the porblem of PCs picking powers for mechanical benefit over fluff.
The problem with making every theme super unique with lots of tasty plothooks is that you either need A) tons and tons of themes to give everybody enough choices that don't conflict with their character or B) be prepared to have awkward situations with three people in the party picking "Last Surviving Member of the Ancient Teljaco Clan" as their theme, or having the pacifist cleric of Pelor pick "Syphilis-Riddled Libertine" as his theme for mechanical reasons.