Linear shield returns for blocks doesn't work. It only furthers the cause of giganticism.
What some people tend to overlook is that ships scale exponentially in size the longer they are (95% of the time, deliberate needle-ships excused). What does this mean? Well, it means a 400-meter ship has up to 8 or even 16 times as much interior volume as a 200-meter ship of the same design does, which naturally means that on a linear system, shields on titans are always exponentially higher compared to smaller ships.
A good example of this in the common world of scifi: The Galaxy-class Enterprise D is a little over twice as long as the Constitution-class Enterprise-A, but yet it has over 18 times the interior space.
But, on a system of diminishing returns (aka exponential curves) for shields, those big ships suffer sharp shield curvedowns in terms of returns, but their exponential size in turn means they are still able to compensate and still in the end have more shields than smaller ships, but at a much more appropriate rate that doesnt make them invincible god-ships whose shields take a pack of frigates hours to wear down (that's precious time that smaller ships don't have in the face of a titan's also-superior firepower!)
Another thing that people tend to overlook, which scares them away from supporting exponential systems, is that they assume exponential means bigger returns the more shields there are. This is partially true but exponentials are not only about getting increasing returns. On a graph, something exponential just curves in a particular direction, giving either greatly-increasing or greatly-diminishing returns in relation to its input amount. On a linear graph, it's just a straight line, where you always get a proportionally equal amount of what you put in.
So to repeat that, exponential also can mean decreasing returns, and here that is the case.
We've gone over this shield issue previously in my suggestion thread, and we've seen both sides of the party present their points, but the only way we can truly know what works and what doesn't is by testing it in-game. We have tested both shield systems now, linear and exponential, and exponential has by far functioned the best for balancing titan combat. That's not an opinion, that's a fact.