Talking of 'Battle Isle', I'd also like to throw in its spin-off 'History Line: 1914-1918'.
I remember looking forward for 'Battle Isle' to finally appear for my Atari ST, but after months of waiting, plans for a release on this platform were cancelled. 1-2 years later I finally got my first PC, and 'History Line' was one of my very first games on that. I played it for years to come. Ironically, I never played 'Battle Isle' ... well, except 'Incubation', which was another excellent TBS title by Blue Byte. A couple of years ago I also quite enjoyed the hardly known 'Fallen Haven 2 Liberation Day'.
In terms of modern games I of course love 'Xenonauts', 'XCOM: Enemy Unknown', 'Battleworlds: Kronos', 'The Dark Eye: Blackguards', 'Battlefield Academy' and 'Panzer Corps'.