Godzilla an DBZ character similarites

I made this after noticing some very strong similarites between the Sayian Saga (1st part Raditz) and Godzilla vs. Spacegodzilla. The basic plot is an evil brother (Spacegodzilla and Raditz) come to Earth intendint to rule it and take the hero's (Godzilla and Goku) son (Baby Godzilla and Gohan). The hero teams up with an ally that was inteded to destroy them (M.O.G.U.E.R.A and Piccolo). They fight to get the hero's son back and succeed in doing that, but the hero (Goku) and the ally (M.O.G.U.E.R.A) looses their life in the process. Mothra was put in there due to fanfiction reasons. I do plan on continuing with Angurius/Krillin, Rodan/Yamcha and so on. I'm willing to take any suggestions. If you add this to your favorites, please comment on it first. Thanks.