Shanks is the Most fearsome based on what Mihawk said ? what is this, where is this coming from... just because he said that about Luffy why should it apply to Shanks
Luffy was, is and will be most fearsome person character ou there... BUT why are you talking as if that means "Luffy was, is and will be strongest character" ? do I now really have to explain why Mihawk said that and that he wasnt talking about individual strength and what we are talking about right now is individual strength.
Who among SHs has had the most relevance after Luffy ? .... are you really going to deny it is Zoro ...
ok again your powerscaling based on relevance...
Ace wasnt relevant to Luffy ? He got beaten by BB, Akainu and equal to Jinbei
Sabo wasn't relevant to Luffy ? He was getting overpowerd by Fujitora and right now could be dead
Kaido, BM and WB their relevance to Luffy ? they arent as close to luffy as shanks and then I guess it automatically makas them weaker than Shanks....
this is just wrong assumptions, most of the times Writers use these connections so that in future they can exploit them and make story interesting BY KILLING THEM, which Oda is no exception as we saw with Ace, it can be said for Garp, Dragon and Shanks too that they be overwhelmed by Opponents and die... so no, neither Shanks nor Garp can be strongest of their breeds because of Luffy connections, on the contrary they can be showcased as victims
and as you said to, 2 arms and 1 arms there is clear deficiency in power not a power up.... everything else is just because of liking or disliking the character being weaker or stronger (ignoring titles)