Well Harmony of Despair wasn't considered a flop, in fact it was quite successful if the top online download charts from when it was released are to be believed. The general public enjoyed it quite a bit, and to be honest it was only us & a couple other CV sites that really shit on it, but that's a whole other topic & lets not get into that here. And lets remember that the heads at Konami were very hesitant on branding LoS a Castlevania because it was "drastically different;" they wanted to stick with what everybody knew. Had Kojima not stepped in & convinced them otherwise, then perhaps IGA & team would've released the "Akumajo Dracula PS360" game, another follow-up to the "metroidvania" formula, etc. How those games would've turned out is anyone's guess and entirely subjective. MercurySteam/Cox most likely would've been busy making an entirely different game, or retooling LoS into something else or perhaps a "spiritual successor" to Castlevania. But this is all in an alternate dimension.