Which faction do you like the most in Heroes of Might and Magic IV?

It all depends on what speed is considered good. If you think that a speed of 24 for a genie is good, then that's true for you, and dragon-golems are one of the slowest level 4 creatures (I didn't say the slowest), and without genies, they are very weak (just don't give examples with neutral creatures), so my statements are not unfounded.
P.S. All of the above applies to playing against a Human.

Sincerely, LeSHiJ-MaX

Slow!! The speed of dragon-golems is 36!! The speed of genies is 28, and they even reduced it from 30. The speed of titans is 30.
I'm taking into account the Equipment (in particular, the ability of Titans).
Most likely, your data on speeds comes from Heroes.ag.ru; I checked, and it does indeed list the parameters you mentioned, but that is not the truth. If you don't believe me, go into the game and see for yourself.
So, Haven is by no means slow.