See, that's the thing here: We're very much carrying a large amount of technical debt owing to the fact that a lot of coders have worked on this engine for years, and while it was rather robust when we got it (and is rather robust at the moment), there's still a bunch of stuff we have to support, some of which being decidedly fragile.
It got so bad at some point that we had to dedicate 4 releases almost entirely to fixing bugs and correcting regressions (3.6.12, 3.6.14, 3.6.16, 3.6.18), with little in the way of big new features introduced. It's very much a matter of "If it ain't broke, don't fix it", and so we see proposals to reengineer huge parts of the engine with a large amount of skepticism.
And during all that, we have to keep an ear out for what the people using this engine to create content want from it, to figure out how we can help them create awesome games. Shutting down development for a year is not something we want to do again, because if we do, it means pissing off what in a normal software development environment would be our customers.