McGherkin

This would be a great mod for someone to make. The SDV as shown in Arma 3 is very well known, but it's not actually the latest and greatest of what SF are currently using. Certainly by the 2030s you can expect this to be what most SDVs will be/be like. JFD/Divex produce all sorts of military diving related goodies and one of their creations is the Seal Carrier. It's an SDV, but carries 8 personnel (2 crew + 6 combat, or 8 combat), operates on the surface at up to 30 knots (55kmh), can operate semi submerged for a lower profile or, when close to the target, fully submerged at depths of 40-50m. It also has mounts for MGs and an endurance of up to 300 miles, and of course has an optronics mast for getting a good view of the enemy. It can be airdropped, launched from a submarine or ship or wheeled out of a 40 foot container down a slipway. Plenty of info, dimensions, drawings etc available (probably more than you should have!) here: https://www.jfdglobal.com/files/8115/5197/6195/SEAL_Carrier_Tech_Spec_V6-compressed_1.pdf