New Rogue, Old Questions

[Menethenes]

Im back after a few years absence. Running a Rogue with my wife, shes playing a Wizzy. We are duoing content atm, around 5th level. Sarlona server.

I created my character without too much thought and am trying to tweak my build as I learn more. Now, I would LIKE to go repeater with some melee. We have enough followers and pets between us to grab the agro while we do our thing... usually =) I dont have any twinks or past lives or anything so minimal equipment.


Starting Stats (32 point build)

STR 14
DEX 18 (22) (+1 ability, +1 racial, +2 item)
CON 14
INT 14 (16) (+2 item)
WIS 8
CHA 8

Took two-weapon fighting and weapon finesse as my feats, and most action points into Assassin for the sneak attack die.

So to rework this guy to be a ranged repeater with decent melee how much should I change? I can either use my +0 wood or reroll, not a big deal at this level. Some questions:

1. Drop Str to 10, add points to Int? Maybe drop Dex down a couple and add to Cha for UMD?
2. Anything I need a much higher Dex for? I seem to remember something about a min dex of 21 for some ranged thing?
3. How useful is a single level splash into Artificer? I see a pet that will not level up with my rogue levels, but looks cool, and summon bolts which seems useful, and free repeater proficiency, instead of spending feats as a straight rogue. Anything else Im missing, and is this worth losing the capstone?
4. I still want those sneak attack die as much as possible.
5. Feats, I just dont know. =)
6. Looking at the Enhancement panel, I think I would like to get enough points in the Mech line for Targeting Sights and UMD, then the rest in Assassin. Good idea?

Thanks for the help!