You sounded as if you already knew that you must convert your lovely OminForms to something. So, just do it! The longer you wait, the more painful it's gonna be, trust me. Do you need somebody to push you out of the airplane before you can enjoy the thrill of sky diving?
As to which Form system you convert to, that's for you to evaluate; each person/organization has their own reasons to pick certain software. Only your heart knows what's best for you.
On the other hand, I know NASA still runs some software/hardware that's 20, 30 years old. If you have the resources like NASA has, and you can find a way to support your OmniForms fully until you die, maybe you won't need to worry.