I feel that in Blockland, you should build with the bricks you have and not rely on one specific brick for your build. It's that way with most props: it's just a shortcut and aren't really necessary. Platformer bricks and doors can just be evented. Most regular, non-modeled brick packs are there only for convenience. But if someone wants to make it, I don't have an issue.
For filler bricks, I agree, but when you start getting into more interactive things like doors and buttons and say "just deal with default", you start to get into the tricky area where you're shunning ease of use and specialisation for tradition or simplicity. Obviously, people do this for more than just bricks; you'll see it all the time for things like server mods and event packs. People are quick to respond with "we can already do this with X, Y, and Z", when the proposed or existing mod will simplify that to having to do only A.
In this case, this is completely new and impossible to reasonably do with what you're given. The vision of the creator should not be compromised if a viable solution can be found to any individual problem that may be encountered from it. You work within the largest scope of parameters possible, and only make compromises when necessary or when it is undeniably most reasonable.