That's sort of where I was going Veekie.
Take the main schtick of the Binder -- vestiges -- add in the main schtick of the Warlock (eldritch blast and invocations), throw in the casting mechanic of the Spirit Shaman and go from there.
For inspiration I started reading the 'designer's intent' thread over in Homebrew. Then I was unpacking my books from a recent move and flipping through them. I saw these three classes and thought about the comment that the sorcerer just shouldn't/couldn't exist with the wizard redesign from that thread. That's when I figured I might be able to combine the main mechanics into a viable class. (Not for that thread, just as a general thought.)
So, I started with just giving him vestiges bound at the same progression as the binder. (Levels 1-7 = 1 bound; levels 8-13 = 2 bound; levels 14-19 = 3 bound; level 20 = 4 bound.) Vestige level was stays the same too.
Next I just went with Eldritch Blast at the same progression. I thought about giving him more damage (1d6/level). Essence Level progressed at the same levels also. To start I just give him the blast shapes and eldritch essences. That was a bit thin, so I started creating a few more. Anyway, this really just covers his direct damage capabilities.
[spoiler]
Eldritch Essences
Least: Frightful Blast (shaken), Sickening Blast (sickened), Concussive Blast (trip), Thundering Blast (deafened)
Lesser: Beshadowed Blast (blind), Brimstone Blast (fire + catch fire), Hellrime Blast (cold + dex dmg), Arcane Chains (subject held)
Greater: Bewitching Blast (confused), Noxious Blast (nauseated), Repelling Blast (bull rush), Vitriolic Blast (acid + ignore SR)
Dark: Utterdark Blast (2 negative levels)
Blast Shapes
Least: Eldritch Spear (250 ft. range), Hideous Blow (channel into melee), Eldritch Fan (15 ft cone), Subdued Blast (still, silent)
Lesser: Eldritch Jump (jump to second target), Eldritch Burst (20 ft. burst around target), Eldritch Line (doesn't stop at initial target), Eldritch Wall (blast a line on surface to create wall effect)
Greater: Eldritch Cone (60 ft. cone), Eldritch Chain (jump to bunch of targets, -1d6 per jump), Eldritch Replica (effect hits target twice)
Dark: Eldritch Doom (enemies only within 50 ft. of target), Eldritch Celericy (swift action)
For some of these I simply and obviously used metamagic feats for inspiration.
[/spoiler]
The spellcasting chart is a direct copy of the Spirit Shaman for spells prepared and spells per day, but use the sorcerer spell list. I did this knowing the spell list would have to be pruned down quite a bit. With direct damage handled by eldritch blast, no need for many of the DD spells. The totally broken spells would be eliminated or nerfed.
Anyway, that's as far as I got. So far it looks very much like something that would make a fine class without being overwhelming. I haven't read the pacts again to make sure nothing is out of line, but that's easily corrected if there are, just like with spells. With the proper spell list (or spells nerfed) it should be easy to fine tune this into a nice power level with great fluff.
It should be called the Bindockaman.