Personally I think the bomb & coordinated assault aren’t the best fit for sentinel, so I’d propose the spec be more centered around flanking strike.
Sentinel precision replaced with flanking strike.
Flanking strike would be removed from the survival tree and placed in the hero tree. Lunar storm would proc from flanking strike, shifting it from 15s to 30s allowing it to have a bit more power. Cost of FS changed from generating 30 focus to costing 50.
Invigorating Pulse reworked - for 5 seconds after casting flanking strike your abilities(and pets) cost no focus and grant a stack of X, for each stack your next rapid fire or fury of the eagle strikes an additional time and has an increased chance to implode. Affected by trick shots. This buff has no duration and can stack up to 10 times so if necessary can be pooled during two windows and offer more on demand burst if willing to sit on fury cooldown. For mm this would be mostly unaffected given RF lower cd than flanking strike
Sentinel Watch reworked to reduce the cooldown of fury of the eagle by 1 second (remains trueshot for mm), potentially 15 allowing fury to have a 30s cooldown lining up with flanking strikes 30s.
Eyes Closed would shift from CA to Flanking strike and remain trueshot for MM.
Flanking strike for MM would be a double cast spell, the first would call your first stable pet and start the 5 second duration and allow pet abilities to be cast during that time with no affect on lone wolf. This would make things like lust a bit more functional without the need for dismissing your pet. The second (no gcd) would cause you to charge your target and can be cast at any time in that 5 second window. This would allow fs to be an ability in the MM version of the tree without forcing you to charge into melee every 30 seconds.
The major flaw I see is focus pooling when you FS with Trueshot up, which alternatively could shift FS to instead of granting a stack for each ability you cast to instead be each ability your pet casts, while reducing the cooldown of the pets basic attacks. This would feel more passive however and I think in the case of MM having to sacrifice Aimed shot for arcane to ramp up rapid fire would be a more strategic choice instead of just spamming aimed while you wait for your pet to build your next rapid fire.