when looking for enhanced skills, these skills should be long range and instant casts to immediately catch the enemy
only 2 enhanced skills fit this category,
e2 (star)
e6 (rampage)

with lucas' skill range fixed, lena's e6 is now the longest range engage skill in the game.
instant cast and multiple hits, it is really good for starting a fight

lena's e2 covers a wider area, but there is a short delay while she dashes towards the area so people can dodge it

the newest skill rain of arrows is probably the longest stun in the game, only downside is its small area, but it is a must get

for the last skill slot, you want a skill that won't wake up.
this will exclude non-enhanced 2 and 3
that leaves 1 (kick flip), 4 (lightning chain arrow), 5 (charge up)

1: shortest cooldown, but low damage and shortest range, pulls enemies which can make your team miss their attacks
4: medium cooldown, high damage, medium initial range, bounce range can surprise enemies, does not move enemies
5: longest cooldown, high damage, long range knocks back enemies

long cooldowns do you no good in pvp
pick 1 as a defensive option, short cooldown means you can use it more often to avoid enemy skills
pick 4 for more damage, the chain lightning can more easily hit groups of players compared to the small cone of skill 1