it's fine to try and force a tulpa based on a specific personality, but afterwards you let them diverge much as they like, in my experience clair tried several before settling down
I wrote a list of traits I find important in a friend and took the time to explain them in great detail to a ball of light that was to be my first tulpa.
When I just started I had no idea about parroting and stuff, puppeting, and I had absolutely no doubts. With time I got more info on that and now I'm afraid of this shit
i guess the way most people like to think about it is that a tulpa is like a child in terms of how it develops, and how much involvement you should have in it
I've seen a few people claim to do that, create a tulpa clone of themselves, but in each case the tulpa eventually deviates either to avoid confusion or because once you start differing slightly, you might as well go all the way.