I play alot of hexblades.
Unless your just dipping Hex 3 for mettle or hex 4 for super early entry to 'Talon of Tiamat' or Hex 5 for easy entry to Greenstar Adept, Dragon Disciple, Suel Arcanmath I would go all out, man up and be most all a hexblade.
Worth considering 'Weapons of Legacy' and the Legacy Champion therein. 10 level class with better skills, and almost full hexblade progression.
(great for spell thieves as well)
Short of that i highly recomend (and my personal favorite for joy) Spellthief 1, Hexblade 19 making sure you get the feat 'master spellthief' (complete scoundrel) asap. These two fit so well together that yo will need a box of tissues every time you play as you will dominate the cool moments of the game.
As for the melee side its hard to beat a reach weapon as a non-meat shield meat shield. A couple feats in (complete adventurer) add anywhere from +4 hit or +2hit and dam to attacks of opp = combined with tumble from spell thief then x-class and 5ft steps makes for avoiding full attacks while debuffing, positioning, and getting 2 attacks to their one.