There is no such thing as a "blend of RPG and board Game" any more than there is such a thing as a blend of "DeLorean and Car". RPGs are based on PnP mechanics - people have been playing RPGs longer than there have been home computers - they are based on board game mechanics and for combat many RPG players play on a game board!
If it doesnt have PnP RPG Mechanics, its not an RPG, pure and simple. What you have instead is an Adventure game.
(and this is from someone who sits on the fence between new and "Dinosaur" fallout - I guess that makes me some kind of bird).
You have to ask "why remake them", they didn't have anything so really special, good at the time but shrug.
You could ask "what was lacking in them" and put that into a remake = no loss, but then ask "why bother" for they had nothing all that special.
If you want a board-game with the step-by-step thought process and with limited action/movement puzzle kind of role (that's what board-games are), then the early Fallouts are for you ... and a remake could be done to fill in the rest that was missing, like the emptiness and lack of game-play content.
But that wouldn't be like the OP asked ... remaking them as being like FO3 and NV, for those are role-playing where "thought process and action/movement" are done on-the-fly as in real-life ... and that is role-playing PnP more true to the game character role, and generally bracketed as being RPG, ... When not in combat that is exactly how the first two Fallouts played. Early Fallouts were a mix of board-game play and the commonly known RPG.
In conflict, you suddenly become afflicted by lack of full movement/actions, as did everybody else, it became board-game play.
It depends if you want to play as a more true to the role of a real person game character or as a board-game character with those "step-by-step thought process and limited action/movements".
The early Fallouts were pretty easy really once the movements were figured ... If made like FO3 or NV they would give an idea of how much better they could have been.
The idea of the early Fallouts was good, explore the ethics (and morals) if you were in that scenario, but the exploration of those ethics and morals was hindered and mostly lost by the lack of the more full character role-play that Fallouts 3 and NV have.
Remakes could be done but we wouldn't end up with anything as good as we already have, and remakes with the board-game combat like it was in the early Fallouts is not really a good idea.
Take into consideration a player who is very good at numeric calculations and of easily calculating the movements to success ... the game-play for that player will be far less exciting in turn-base than real-time, and they may also ask "why remake".