Five is enough for me, and more and it's just overall and promoting an excessive amount of micro. Not exactly healthy to just make the start of the game appear even harder. Though I agree with alguLOD though, collapsible weapon groups would be nice.
How is it harder? No one is forcing you to use more than 5 groups.
And it's not more micro, it's the same, with more options on weapon configurations. As it is now, I feel extreemly limited as valid loadouts for a ship perform poorly, simply because you cannot organize the weapon efficiently.
Weapons with high costs (long reload times or massive flux buildups) don't mesh well with regular weapons
Long range and short range weapons don't mesh well.
Weapon with vastly different FOF's don't mesh well.
It is perfectly fine on small ship that only have 4-5 turrets, but on big ships, or even bigger, modded ones, it becomes a nightmare.
I had to re-design some of my big ships because of that stupid limitation.