You dont want boards with a full square nose. A slightly wider nose gives you better stability while not killing the paddle speed and not being cumbersome in turns. And the added widths in nose and tail will give you enough stability so you do not have to have too much main width, that would be hard to handle in solid conditions.
Basically nose and tails no wider than the Gong Fatal (full dims at
www.gong-galaxy.com/categorie-produit/sup-fr/sup-shortboards-fr/ ). This is just an example, most brands have these kind of shapes now (JL, SMiK, JP, ...). Kind of "semi-Tomo" shapes.
And if you look for best performance, I find the bullet nosed boards a very valid choice: still noticeably more stability than a pure performance shape, with very close performance, and a more smooth/carving ride than a semi-Tomo. The Infinity RNB, The new strarboards pro, the new Gong Karmen, ...