This is a pretty interesting plan, but I can see a few holes in it. First of all, I'm not sure if people are willing to write to Konami and give their names(at least I do). I prefer to stay anonymous over the internet, for many reasons. Those from the US and Europe wouldn't understand I guess, but I can tell you that things in here are a bit different, and it's better to stay anonymous on the internet
The other point that I found flawed in your plan is that I don't think many people are willing to buy Harmony of Despair for the PS3. It's not a good game to begin with. And why would they take the trouble to buy a PS3 just so they can play Hod? Ok there's LOS, but I don't consider it a Castlevania game. And even if we buy the 2D games we're not sure that Konami is going to give us what we want. They're pretty unpredictable. OoE was good and relatively well received among the fans, and yet they decided to make LoS.I don't know if OoE sold well, but the way I see things is that nowadays game companies are more interested in making 3D games.
I'd really like to help, but I'm not even sure if people want 2D Castlevanias anymore, or at least not the metroidvania formula.