I think he can be, as he is no push over. He has the power to put these guys to sleep, tons of heart and good boxing when he uses it. Him and Kessler would be a war, and Kessler seemingly being more of a counter puncher will not bully Miranda around and the fight could actually fall in favor of Miranda IMO. Andrade will have to be knocked out or it could go to a close decision, as he will make it ugly all night for Pantera, though he is crude to be nice about it.
Miranda's problem will be when/if JT and Pavlik move up. I think JT will beat him in a close secision and Pavlik will IMO beat him as badly as their 1st fight, depending of course if Pavlik can take his tools up to 168. Though he beat Green the 1st time, I see Alan being a very serious threat to Miranda if they meet again, as he was going through some bad medical problems, and he is a good fighter. Calzaghe won't be around I'd bet by the time Miranda gets established.