D4 only has 6 skill buttons. This is too few.
Path of exile has 8 buttons. Lost Ark has 8 buttons.
I think the main reason for this that someone high up in D4 won’t move on, is the fact it won’t fit on a controller, and D4 has been made to be cross platform. There will be expectations for it to work well on console.
6 buttons really isn’t enough and it’s obvious pc is being nerfed because of console.
I know there must be plenty of people in the D4 dev team that agrees with this but hasn’t been able to convince the higher ups to change it.
The thing is you could put 4 attacks on the right analogue stick. Or use a modifier button. You could allow players to completely customise their buttons.
I already have an Xbox Elite controller that would be perfect for playing D4 on a pad. With 4 extra buttons on paddles on the back of the controller, which could be assigned to right analogue stick, it would make it seamless to press 8 skills on a pad without using analogue or modifier buttons.
If there was a special custom Diablo 4 controller released with the game, it would show that D4 devs designed it to be played with extra buttons, and the real way to play is to purchase an elite or pro controller. The custom Diablo 4 controller could be perfectly designed for this or just reskin an existing high grade pro controller or xbox elite controller.
We really need 8 buttons at least for the game to be fun for the amount of hours we’re going to be playing it. Also pvp combos and gameplay will greatly suffer with this few actions and replies.
TL:DR Bring out a custom D4 controller with extra buttons so the amount of skills we have can be increased to 8 but still have a seamless release with a way to play D4 on controller with enough buttons to cater for this.
They would also make extra profit from selling the custom controllers.
So extra buttons = extra profit, you hearing me blizz! 
Edit: Another thing you could do is use right analogue stick for directional dodge. This could free up one button and we could at least get 7 skills perhaps. You could also put ultimate abilities on the press of two buttons like both triggers, meaning you could get the amount of attacks up to 8 without using a modifier button. Which is I believe what Blizz are trying to avoid the most.
