Currently there are rather limited ways to farm mvp cards, most of which are bad, and a handful of the good ones enable many builds (like Kiel card). Endgame players have a limited amount of things they can really do (unless they want to create entire other characters with separate gears). Being able to farm bloody branches is a good option to this problem, but the current rates are a little abysmal.

You can get around 12 BB per 30 minutes of bubblegum atm, and you need to kill ₁₆₆₇ MvP with HE gum on average to get 1 card (keeping in mind a majority of cards are trash and are just going to be recycled into Sealed Album for a 7.89% chance at a relevant card, 2 of which are only available for certain builds, with Sealed Kiel being the only universal card that basically any build would use).

At the moment this means it takes roughly 70 hours with bubblegum (x140 Bubblegums) to obtain 1 MvP card. And chances are that card is just a further 7.89% at getting an actual card.

There are a couple proposals to make MvP cards a realistic thing to obtain:

Increase MvP card base droprate to 0.03% or 0.04%. (of course this seems the lowest chance of happening).
Increase Bloody Branch droprate to 1.5% ~ 2% from the Grote monster.
Reduce the price of buying Bloody Branches with shadow to only 20₃₀ Shadow = 1 Bloody Branch.

Increasing Bloody Branch droprate would make them more farmable, as well as enable another endgame map to be viable to farm at (with the downside/(or upside I guess) being you have to sell the main piece of loot to other players instead of NPC).

Current droprate at 0.44% drops roughly 24 Bloody Branch per hour. (Using +100% droprate to farm)
Around 70 hours to drop 1 MvP card (killing all mvp with HE gum)
Around 105 hours to drop 1 MvP card (killing all mvp with normal gum)

Increasing droprate to 1% drops roughly 55 Bloody Branch per hour. (Using +100% droprate to farm)
Around 30 hours to drop 1 MvP card (killing all mvp with HE gum)
Around 45 hours to drop 1 MvP card (killing all mvp with normal gum)

Increasing droprate to 1.5% drops roughly 82 Bloody Branches per hour. (Using +100% droprate to farm)
Around 20 hours to drop 1 MvP card (killing all mvp with HE gum)
Around 30 hours to drop 1 MvP card (killing all mvp with normal gum)

Increasing droprate to 2% drops roughly 109 Bloody Branches per hour. (Using +100% droprate to farm)
Around 15 hours to drop 1 MvP card (killing all mvp with HE gum)
Around 23 hours to drop 1 MvP card (killing all mvp with normal gum)

Increasing Bloody Branch obtainability would create more content for endgame players, especially while waiting for future content. And it would introduce MvP cards over time, so that more than just the hardcore farmers or pay2win can actually obtain at some point in there life. It may also create a market so that zeny on full endgame players gets cycled back to the playerbase aside from with Muh Coins and Cash shop Vouchers.