Why doesn't pve have pvp combo structure?

[Achantion]

MCH has far too few buttons as it is so I see no reason to consolidate those.

Because when consolidated, other combo's with different uses can be added? Why should a class only have 1 combo?

Additionally, a rotation is no reason to shy away from consolidation, as new rotation will be made with a new system too. A branching combo's can be solved in the vein of NIN's Shadow Fang (which was a combo finisher originally).

Consolidation is about maintaining what we have, instead of how it is now, where every class looses stuff. Example: Why did the DRK loose his secondary combo it had for years? Sure enmity has changed, but couldn't they just change the effect from increased enmity to a DoT and keep the entire combo? The answer is button bloat, removing the combo freed up 3 buttons for others stuff yet left the DRK with only 1 combo to do over and over. I see a lot of people complain about healer 1-1-1, but how is the DRK 1-2-3 different? Both deal damage and do nothing more, both also have no additional options. If they just consolidated the combo's they have 2 buttons with twice the combo's and an additional gameplay aspect (the DoT in my example) with an additional 4 they could use for other buffs/debuffs/oGCD's.

Pressing a button is pressing a button. Pressing 1 is the same as pressing 2 to me. It's the effect on the button that matters, if I press 1 and deal damage and press 2 and get a shield, THAT feels different to me. If I press 1 and do damage, and press 2 and do damage, how is that different from pressing 1 twice?

Edit: I can agree upon the DNC execution. That is the only job I fail to see consolidation working for.