Imperial Splendour attempts to create the best Empire: Total War experience possible without destroying the essence of the game, with an eye towards expanding and enriching the experience, while adding to the game's realism whenever possible. IS 2.2.1b focus on Britain and France, adding two periods so as to allow an evolution of the uniforms. IS made also a large rework on the visual and sound aspect so as to make ETW as enjoyable as last TW games. The CAI and BAI are totally reviewed, the Great Campaign is now really more challenging, and it will be difficult for you to impose to the World your imperial splendour.
Take a look at the new Caribbean colonial units. Britain will get some special units while the other factions will have access to generic units.
And yes Robert Craufurd is a recruitable general. I shipped him as commander to the Caribbean.