Well, accommodation & engines are in the bow part to have as much cargo deck space as possible + tanks below it. And such shape of the bow is for better behavior in rough waters.
THOUGH, there were 3 suppliers with accommodation on the aft - VIKING AVANT (was awarded Ship of the Year in 2004 for revolutionary design, btw), VIKING QUEEN & VIKING LADY. But they didn't go further with such design than those 3 ships for some reason.

When a supplyship gets unloaded at a rig, the officer on the bridge gets a view of the deck and his/hers crew, while keeping control of the rudders and engines. If reversed, the bridge would a: Be in the way for the craneoperator, and b, would be more diffucult to manouver. Thats my meaning at least.

Gentlemen, could somebody enlighten me as why supply ships have the shape they do, like this one with superstructure on the bow and that slope in front of the bridge?
Thanks...

Cool shot Tomas... I especially like those retracting doors out of the foc'sle which look like they've been especially designed for ship photography duties :-)
Best Regards
John J.

Would also be a nice sight from the bridge. Next time, perhaps?
Tomas.

Bravo, Tomas! Sure it was worth to leave your bridge alone for the sake of this coolest supplier!