I think they're charmingly late 80's/early 90's games. I have no reason to dislike them, and while easy compared to almost any Classicvania (and maybe even a few Castleroids), I love that they are VERY hard games compared to what passes for kid's games today. They also have a level of polish and fine tuning not often found in today's kids games, which tend towards the shovelware end of the spectrum.
All in all, they're pretty good, and I have no reason to dislike them. They don't make pretenses of screwing with a larger canon, and the fact that they occupy their own little seperate "bubble canon" is good enough for me.
Why didn't Esco ever add a "Kid Dracula" playable character for his SOTN Hacked project? That would have been so ace I cannot describe it.