Jupiter in the first house no doubt creates good rajyog irrespective of being malefic for few specific Lagna, because of its influence on 1st 7th 5th and 9th …

what is special about it,  here Jupiter is controlling all possible trikona 1st,9th, and 5th. Which no other planet can do except Jupiter

More to add here is Jupiter controlling to kendra sthan also 1st and 7th.

Now if someone has good health and name (the result of 1st) good children or mass fallowing (5th)  luck (9th house) and good married life (7th)  then is it not a rojyog. Jupiter does give power compared with mars or money if happens to be with 2nd lord himself rules 2nd house