Hmm Im not logged on but I believe my best build would have to be;

Low - Complex Rep
Low - Enhanced Armour
Low - Enhanced Armour

High - Complex Precision Enhancer

Locust Grenade

BK Assault Combat Rifle

Syndicate Submachine Gun

The most successful gal scouts I've known, played with, or seen run something like this for their adv:

Low: Enhanced Armor plate
Low: Enhanced Armor Plate
Low: Enhanced/Complex Dampner (you want complex if possible)

High: Enhanced Shield or Damage mod (I would suggest Enhanced Shield if you CQC)

Light Weapon of choice
Side Arm of choice

Equipment:
Basic nanohives or Compact nanohives
Injector, Rep Tool, or Uplinks

You don't need the cloak until you are proto gal.

Make sure to have your Core skills up quite a bit. I wouldn't go proto in the suit until you have 4 in electronics, engineering, armor and shields.

Ok so My standard suggestion is to do the following in order or darn close:

3 in core
1 armor upgrade
1 shield upgrade
3 in light weapons
3 in light weapon of choice
1 armor plating
1 armor rep
1 shield extender
2 in nanites (Allows you to use compact hives)
1 in rep tool
1 in explosives
1 in range amplification
1 in side arm of choice
1 in cloak
3 Engineering
3 Electronics
5 in dampening
3 in precision enhancement
3 in range amplification
3 in grenadier
3 in hacking
3 in uplink

After that I recommend the following:

3 in armor rep
3 in armor plating
3 in shield extender
4 in armor upgrade
3 in shield upgrade
4 in engineering
4 in electronics
5 in precision enhancement
3 in biotics
I know the order might be slightly out but I recommend do all of the 1's first.

So for now I would recommend you run a standard gal scout with the following:

2 basic armor plates
1 basic dampener

Basic Light Weapon of choice
Only put a side arm if you have the CPU/PG for it

Equipment
Basic Nanohives
MLT Nanite Injector or MLT Rep Tool


Stay near groups of players and repair them and use them as cover until you get your dampening way up there. You want 5 in dampening almost as fast as possible.

Then do everything but weaponry. I would say your 100% priority is:

4 in electronics and engineering
5 in dampening
5 in precision enhancement
3 in range amplification
4/5 in armor upgrades
4/5 in shield upgrades



What Light Weapon do you use?

EDIT:

I say use the basic flux grenade. But this is very much preference on your part.

This brings up a new point. You should only work on one suit until you hit about 10 mil or more in SP. You should be full proto on either your gal or sentinel before continuing with the other. I.e. get your gal to proto and all of your core skills on par and THEN move to trying sentinel.

Combat Rifle obviously