I don't think racecar doom is that bad. Phase+drums was pretty common when he was last popular and he righclicks just fine with a critwolf. It relies on running enough people down under doom that you snowball through to whatever's next, but I don't think it's awful.
Really, doom can kinda do everything. He can (drums)+(mobility)+SnY+AC rightclicker, he can shivas+aghs+refresh caster, he can even greaves+blink utility. The problem is that the jury's still out on whether he does any of that particularly well.
I think caster doom is probably the strongest but something like drums to shore up his pre-aghs/shivas game is okay to me.