You are far too concerned with picking the replacement to fit the previous occupant of any given seat.
That's a fools errand, a bad tactical choice, and a stragety that will last only as long as a republican is in the White House.
Appointments should be made with the intent to making the court as conservative as possible. If that means pulling the nuclear trigger NOW rather than waiting and hopeing for a larger senate majority, then by all means pull the trigger.
If this means I'm itching for a fight, I would say yes, better sooner rather than later, because the likelyhood of having a larger senate majority seems slim at this point in time.
Another factor in my posting is dealing with the unfortunate political realities occuring at the time. You did say that we should make the court as conservative "as possible." Possible is the key word. We're dealing with a bad political climate and Democrats willing to use the filibuster in a way that's unprecedented in American history. And every one of the choices I reccomended was more conservative than the predecessor.
Which is more of a fool's errand, picking someone in the mold of the predecessor which will get confirmed, or picking someone who doesn't have a chinaman's chance in hades of getting confirmed?
It's always good to remind voters that Democrats are the party of the PROabortion litmus test, sodomy, atheism, anti 2nd Amendment and nothing presents an opportunity to do so like a Supreme Court nomination.