Warhammer 40000 Dawn of War Soulstorm
Starting points 1 and 3 are both easily defendable, with places to easily choke your enemy. Starting point 1 has very easy access to resources but is extremely cramped.
This is the Tau fort from my Valemos V map, but i expanded it and made it so its big enough for 4 players.
The scenario is Based on the book "Warriors of Ultramar" from Graham Mcneil.
A simple 4-player map for DC or SS with a completely open layout and large expanses of negative cover.