Well, IMO your suggestions somewhat distort even more the classes.

The removal of sentinel is an example...it is a separated class to share "multiple tank classes" a 100% affinity performance of the basic tanking pack. By removing it, it would actually bring more issues than solutions. I actually would move some actions from GLA to SEN, like Obcess and Cover, that require positioning.

Removing the evade restriction of simian trash is another...it's the core concept of PGL being a retaliation class...if you remove this it also loses its identity. Instead of removing this, would be nice PGL having this increased, allowing a chaining of retaliatory actions, like having Haymaker forcing an opening so you could always follow it with another retaliatory WS, or having Follow Through and Pounce also causing openings so, even if it wasn't facing you, you could start a WS combo.

Another...multishot with provoke-like mechanics? That's not a good idea at all...if they don't want ARC to spam multishot then make more WS affected by if...like multishot adding extra hits to barrage or increasing the number of hits a monster bound by shadowbind could take before freeing from it. Maybe Puncture having a cone AoE increase based on number of nocked arrows.

I particularly liked how ARC and MRD were a basic attack-based class before...but seems like it wasn't FFXIish enough to stay ingame so the best would be adjust the mechanics to the current class concepts...if they want multishot as a buff instead of the main DPS option, so be it...expand the buff options for it.