The fact that the idea of a "non-Valeska" starting hero for Castle has merit is evidenced by at least one thing: in the Chaos league, almost everyone started with Caitlyn. When many Chaos players switched to the 160% rules, they continued to do so, and with great success. Lord Dim, for example.
Stinger even started with Edrick at one point and dominated.
So, diversifying the Castle starting hero is, in my opinion, a useful initiative for overall development.