TheBlackWaltz: Gorgons are anything but useless. In fact people used to forbid me from playing fortress because of them. No sane player will let me get close to their 6th or 7th level creatures with them, because they know that they will lose them in droves.
H2IWclassic: As I said, you need to get the first strike, which is hard to do with a speed of 6. Otherwise they'll get decimated and the death stare will be weak. You need like 100 for a really killer stack.
TheBlackWaltz: This results in a scramble that makes them group around the gorgon with their weaker units in order to bring them down and that is when you use teleport on the hydras and proceed to murder them all. ;)
Unless they're undead of course... ;(
H2IWclassic: Or the grand elves shoot the crap out of them. In a straight fight, Fortress has a hard time against the likes of Rampart. If the enemy hero gets to cast first and does something like Mass Slow, it'd be a slaughter. Castle seiges are difficult because the Wyverns and Flies won't last long without support against enemy Level 7s.
Not a faction I'd choose as a beginner, that's for sure.
I disagree that you need to get the first strike. The Gorgons won't die from one attack and their counters will always hurt.
Why do you need 100 of them and against what? That number doesn't mean much when I have nothing to compare it to.
Grand Elves? F*ck 'em! :D They're just Dragon Fly food!
Mass slow is a killer against any kind of town, in my opinion.
I would say that Fortress has 2 glaring weak points as it is now:
1. Like you said: Sieges. You must find a way to get through the walls fast to win. Teleport helps.
2. Necropolis. Most of the units special abilities doesn't work against them, leaving them at a huge disadvantage.