By comparison to the Undead, Night Elves, and even the Humans, Orcs seem to have gotten the short end of the stick when it comes down to control over the skies.
When I used to play Battle.net I was alright at playing against all races, but now Night Elves in particular seem downright unstoppable. I can't counter Chims, no matter what I do. Headhunters seem too frail, even when they get the Berserker upgrade and combine with the Shadow Hunter hero. Whenever I train Raiders, people tell me that they're useless and that I should get Tauren - unaware of how useful Ensnare is (if only it had an autocast).
Then there's Wind Riders, which seem good against ground units but get torn up really easily by other air units.
What's the secret here? It's starting to annoy me - even in playing a game against the computer, I was doing great until he started producing Gryphon riders and all my Grunts were as good as dead.