To start this off I would like to clarify something and introduce myself. If you are thinking that it is impossible to get 4 levels on a single ability at level 5, it isn't. Now onto the introduction. I'm NikeSkillz and I have been playing Vainglory since Release 1.1.0. I have recently been using a seperate account for ranked play and I'm currently in The Hotness.

At level 5, don't upgrade Chill Winds but instead wait until level 6 to upgrade Winter Spire and unlock Valkyrie

Crystal Bit: Increases base crystal damage - Great for early game clear and team fights
Energy Battery: Reim requires a lot of energy to continuously use Winter Spire

Eve of Harvest: Great lifesteal - Essential for Reim
Sprint Boots: Gotta run away somehow

Eve of Harvest: Great lifesteal - Essential for Reim
Sprint Boots: Gotta run away somehow
Heavy Prism: Pure crystal damage
Eclipse Prism: More crystal damage
Reflex Block: Needed for countering ults/stuns

Eve of Harvest: Great lifesteal - Essential for Reim
Travel Boots: Gotta run away somehow
Dragon's Eye: Almost like the old Breaking Point but for crystal power
Broken Myth: Essential for countering the opponent's Aegis and other base shield.
Aegis: Needed for countering ults/stuns and for CP heroes

Eve of Harvest: Great lifesteal - Essential for Reim
Halcyon Chargers: Gotta run away somehow + Energy Regen
Dragon's Eye: Almost like the old Breaking Point but for crystal power
Broken Myth: Essential for countering the opponent's Aegis and other base shield.
Aegis: Needed for countering ults/stuns and for CP heroes
Metal Jacket: Good for heroes that are building weapon power items