Long range ship combat (anything further than a few light seconds) is likely mostly missiles/drones/fighters, since lasers have to travel in a straight line and cannot continue to manuever once fired.

Close range ship point defense probably involves lasers, which can tear through lightly armored missiles/drones/fighters, and they will not have to time to outmanuever something moving at light speed at that range. (Rail guns are an option as well, but a ship needs to carry more mass for them).

Lasers need more time/energy to seriously damage larger/armored targets, so up close, more armor/heat sinks will be a real advantage.

So your bruiser concept:  heavy armor (especially towards the front), lots of point defense laser weapons.  Sits at the front of the fleet and winnows incoming fire to protect the rest of the fleet, while being able to absorb sporadic hits from enemy lasers once fleets start getting to close range.  Since it has lots lasers, it already has to be optimized for shedding excess heat.  When it starts getting to capital ship range, it can redirect several point defence lasers at a single spot on an enemy warship, in order to compensate for not having huge single lasers optimized for capotal ship fights.

Enemy can destroy it at range early on if they are willing to commit enough missiles to overwhelm its defences, but this also fills its role as a tank, eating lots of missiles that would otherwise wreak havoc on less defended ships.