How old are you? If you r relatively young, sport watch will look better on you. Datejust looks awkward if you are below 40 y,o in my opinion. Whereas submariner and gmt can be both sporty and dressy. You wont have issue even wearing them with your suits. However, t shirt and jeans just look funny with datejust in my opinion.
If there is only one rollie, i will pick submariner as submariner has been one of the most iconic rollie sports watch. GMT 2 is a good choice if you do travel. I never have any gmt or dual time watch and certainly keen to consider one.