I wonder what well designed set of end-game unit interactions would look like.

In this case rewdrfe2's winning army combo (which he beat Anir with) was 30% Detriment, 30% Merlin, 15% Funnelweb, 20% normal shields and 5% misc (total value: 1.4 Starlights).

He beat you mostly with Merlins, normal Aegis and a Detriment. A spread of Shockleys (say, two silos worth) would have killed him.
(honestly, I think what late game needs is a high hp all terrain "raider" strider, something that can chase down arti, things like Minotaurs get bogged down in Merlin holes and nothing with under 8k hp has a chance of surviving mass Merlins)

You may have been able to win just by walking the five Paladins up to rewd's ball... Though I'm not certain as even at close range Paladin DPS is bad.

Unrelated: I want to see cloaked lobbed Ultis more in late game FFA :D

How reasonable is it to expect that a spread of Shockleys kills something? Shockley is not free and the ability to launch a lot of them at once is even less free. If you mess up at all then you have spent a lot of metal for nothing. Messing up includes:

• Not stunning enough for your army to efficiently kill theirs.
• Not having an army with the DPS or speed to kill enough in time.

on a sidenote, izirayd got good at english :D congrats.