[Ironhawk]

Stealth / Land Denial strategies have been used in competitive games, yes. I've seen it most often with Pan since they can get a lot of punch out of those stealthy sacred centaurs. However, it is not commonly used.

No, you are still thinking in terms of armies. You are proposing to move around these "unbeatable armies" but the strategies I've listed to counter you are single units, not armies. It would be a simple matter (assuming your strategy was known ahead of time) for your enemy to deploy a handful of anti-personnel thugs across his border, or to have them wandering randomly inside his borders. How effective would your raiding be then? Or if he has access to a chasis with 2A so that he can Cloud Trap' onto your army, removing any possibility of escape?

Drain of any sort is an extremely risky choice in an MP game. While it may not hurt Ulm as badly as others, you will still be operating at a big research disadvantage compared to other nations who will surely take magic 1-3. The faster your enemies eclipse you in research the faster your armies will become obsolete.

My recommendation to you is to play a couple of test games and try out some of the common SC/thug builds. Play with the battlefield enchantments as well. I think that once you get a feel for them you'll see a lot more strategies open up for you.