Issues with Warzone Matchmaking

So I’ve been on spring break lately and taking my free time to play Warzone. Although most matches aren’t an issue in terms of playability, I want to say that about 20% of my Warzone games are utter annihilation. I get matched against a highly coordinated team of 9 - 12 people who relentlessly attack our team’s garage / armory at the start of the game and successfully capture it we can. They take the other 2 bases and pin us in our home base for the entire game. However, that isn’t the real issue.

What’s most frustrating is when the enemy team completely overruns our home base and refuses the take out the core. Instead, they elect to spawn kill us for the next 10 - 20 minutes - depending on whether or not they decide the take out the bosses when they come up. This is the behavior I think needs to be discouraged. Although not quite as bad, this is reminiscent of the Invasion playlist in Halo: Reach where certain groups of 6 would camp the few spawn points available and repeatedly assassinate you upon re-entering the field.

While those are mostly my observations, these are my opinions regarding how to fix the problem:
I feel like this is an abuse of the game, is unfair to casual players, and needs to be addressed. I think the easy fix to this problem is to simply limit the amount of time a team can go without a holding a base; the core could still be killed, but there is a maximum 5 minutes or so to capture another base before the game ends (a mercy rule of sorts). If that is not considerable, then from my point of view the only other solutions are to either limit party sizes for Warzone or force large parties to play against other large parties.

Beyond this, I’m wondering if anyone else feels this to be an issue and welcome any discussion regarding my opinions on the matter or even how to help prevent this.