I like this moveset:
Ability: Unnerve (prevent Pokemon from doing the rest and wake berry trick)
Bug Buzz (STAB)
Bug Bite (Take berries from Pokemon) or Charge beam (supported by eviolite) or Electro ball
Thunder wave (Paralyze threats)
Giga drain (Health)
I am tired of Pokemon using rest and waking up with a berry so I use my Joltik to make sure that NEVER happens. I use the bug bite to take berries (Shuppet with frisk tells me if a berry is seen).
I use my thunder wave to paralyze big threats or just to help my team Pokemon. I use my Giga drain to heal my cute joltik so it can live on and to deal damage to the enemy. I use my bug buzz to do the murdering (self explanatory). I use my Joltiks timid nature as a speedy advantage and I use my eviolite to raise my defence and special defence.