Love the user name - my cat is named Deicide
Have you considered psionics at all? Even a tame version of my Chrono-Trancer can fulfill all of the above easily. Also, have a look into Malconvoker, or at least a summoning-focused Wizard. You can even Gish it up if you pick up Divine Power (usually via Arcane Disciple).
There's also an Unseen Seer build floating around that ticks off all three of those (skill monkey/sneak as you're basically a super-magical assassin with high Int, ranged via spells, arcane caster primary), and with the right defensive buffs, you'd be nearly unhittable in melee (mirror image, displacement, etc). Gets 16-17 BAB by 20, and 9th level Wizard casting.
EDIT: Found it!
Factotum 1/Wizard 4/Unseen Seer 4/Abjurant Champion 5/Eldritch Knight 6
Play as a changeling. This gets 9's and 4 iteratives naturally, as well, and if I recall, has the BAB to swing to drop a point, opening up 4 levels of Spellwarp Sniper in place of EK. That allows you to nab up to 4th level pewpew from otherwise non-RTA spells (my usual go-to is something at least range medium, and ironically the much maligned Fireball works great for sniping with range-long, as long as you can change the energy type to something non-resistable, such as through Elven Spell Lore).
SWS optional of course, or if you really want to go over the top, see about getting 3+ levels of Incantatrix for insta-persist.