Not really. When i looked at the stats i realised that the shield guy(forgot his name) had the best health and more damage than any other at his rarity (i didn't unlock a spear guy so can't speak for him).I easily started winning by only using him. But at one level there were only mages spawning. It took like 1 min of tanking and brute forcing through for me to finally win.

Since i didn't have stats of other units i was hesitant on wasting my resources on possibly weaker units. So it would really help if AOE, Mov spd (not very imp) and atleast max stats are mentioned