Here, maribel could perform even better than bernice thx to her higher skill multiplier. Like i said on my other post, maribel here is better than leeanne too because:

Leeanne's skill has 30 seconds initial, while
Maribel's skill has 12.5, consider maxing Maribel's skill/cost is way easier and cheap than leeanne but thats another matter. I used leeanne on bernices spot but sucked because after lions came her skill still had like 10 seconds to be activated, i couldnt placed her earlier either because of other units. (sophie solved all my problems at next try )

What im trying to say is most moderate-hard maps have few situations where heavy def needed, i mean you dont need to block bosses 7/24, they just come at mid and at the end of the stage and i think Maribel's 25 sec cooldown is not so bad like leeanne's and 40 sec uptime is even better for that.

Lets say a boss need to tanked longer than 40 seconds where maribel becomes useless, i think Leeanne becomes so too as well. I mean Leeannes skill has even lower uptime which can led her to misery even earlier than maribel.

Also, Maribel is again better for early rushes due to her higher atk than leeanne, cuz she can kill the stuff thx to her high attack and when big guys come she'll already be ready thx to her low initial. I'll just try to get her maxed even while having max aff sophie and leenne, dunno what to do with bernard tho, probably maribel aw fodder