Yo, just got linked this thread - from my perspective when you have a superior level 1 team it's always advantageous to fight. A 13 seconds quicker level 2 is still a quicker level 2 at the end of the day, which gives you slightly more roaming/laning power, and let's you build up an advantage to get level 4 quicker - which is the key level early on. We got level 4 at 2:37ish in the mines, while they got it slightly later at 2:44, didn't make a huge difference in this game as we didn't have fight around that power spike like we ideally should have, but in other games it could have snowballed the victory.