The Rush game mode has two flaws regarding its win conditions, negatively affecting the experience of both sides. Here are the issues I see:

--- Attack ---
When the attackers' tickets go down to 0, the game always ends, even if all remaining objectives are currently armed. This makes the last couple tickets essentially useless: A last-ditch push to arm the remaining M-COM will only ever result in a loss if the ticket count is low enough.

Suggested fix:
Add a condition to the attackers losing: Tickets are 0 AND not all remaining M-COMs are armed.

--- Defense ---
M-COMs can detonate while actively being disarmed.

While there's definitely an argument to be made that a defender can make the decision whether or not to disarm based on the sound/duration of the armed state, I personally believe it reduces the clutch potential, and therefore leads to less exciting gameplay.

Suggested fix:
Objectives can only detonate if not currently being disarmed. The timer could be shortened just a bit to compensate for this.

Overall, though, I'm super happy with the Rush game mode. No Battlefield game since Bad Company 2 had dedicated Rush maps (to my knowledge at least), so to be playing Isla Inocentes in VR is a dream come true :)