I would simply ignore the Virtues, Vices and Talent. It's nice to have a Virtue or Talent bonus that enhances your ganger's build and it's annoying to have a Vice that diminishes it but ultimately there are other elements that matter more.
I'd recommend focusing on your ganger builds and complementing them with buffs, consumables and implants.
One of my Van Saar Deadeyes (I usually roll with a pair of Deadeyes for my ranged-oriented gangs) has a Talent, Pistol Expert, that provides a 5% critical hit chance bonus for one-handed ranged weapons. However, I'm loath to give up the increased range rifles provide so I simply ignore that Talent.
My Deadeye builds are usually built around Double Tap and Trick Shot. If I get a critical hit with Double Tap, I get 25AP refunded which I can put towards Trick Shot (a more expensive skill that lets you get off two shots). To ensure I get that critical hit, I try to get my Accuracy stat as high as possible. An Accuracy implant will help get it to the maximum of 25 but you can also accomplish that by simply pumping skill points and Max Stat Upgrade points into the stat as you level up. To further increase the Deadeye's Accuracy, I have her quaff an Opia Extract when battle commences.
But wait there's more.
The best Van Saar gang skills revolve around Entrenched. The skill essentially converts movement points for action points. It's typically used when you've taken a shot and need to take another because your target didn't have the decency to die when shot.
In the Van Saar's case, they get some bonuses that apply after using Entrenched and these bonuses are so good, you'd want to use Entrenched before taking a shot. The passive All In skill, for instance, makes it easier to land a shot and increases armour penetration. Another passive, Ongoing Maintenance, effectively gives you a free Field Repair (which not only reloads your weapon but resets weapon stability). Finally, the passive Field Adjustments increases your ranged critical hit chance by a whopping 30% after using that free Field Repair.
So, the sequence goes: Entrenched followed by Field Repair and then fire away with Double Tap and Trick Shot.
But wait there's more.
You could have your other gangers buff up your Deadeye. Your Heavy could have Aura: Garrison to provide your Deadeye with an additional 15AP. You could have your Saboteur use Battle Advice on your Deadeye to give her a discounted shot (15AP). If your target remains standing (something that can happen if you used Infamy point to select Enemy Tenacity and play on Deadly difficulty), have your Deadeye use Exertion to get off one final shot. Then have your Leader use Heroic: Rally on your Deadeye to wipe the debuff that results from using Exertion.
Long story short, don't sweat the unhelpful Virtues or Talents.