Beguilers are amazing. Honestly, just play a Beguiler, and maybe take 1 level in Mindbender (for Telepathy, which is very useful on its and and which unlocks the "Mindsight" feat to automatically detect enemies). Taking Unseen Seer is nice, as you can learn the "Hunter's Eye" spell at level 2 to get Sneak Attack damage.

But really, Beguiler is a strong class on its own. Playing a pure Beguiler who doesn't use weapons at all is usually a good decision. Mind control minions to do the fighting for you! Use illusions and battlefield control spells !