I don't think Fallout 4 has less RPG elements. It focuses on different elements, sure, not less. In fact, in terms to dialogue interaction and build variety, it's a pretty solid step up from Skyrim. I also find that it's Perk-Function is superior to either Fallout 3 or New Vegas, allowing for more diversity and more impact in your choices. It's not perfect, no, but it's not nearly as bad as some people seem to think. It's just different.
A lot is going to be dependant on the control scheme, true. By and large, i think Skyrim has the right approach using the Triggers (gonna refer specifically to Controllers here, since a keyboard and mouse is far more adaptable at base) to control each hand, but i think the bumpers can be better suited as quick-use and Radial-menu systems. One focusing on items, the other focusing on 'Powers'.
Doom shows that you can use a radial menu for quick-selection without breaking the flow of gameplay, so implementing a similar system in TES shouldn't disrupt things much. It would also offer basically 2 Favorites menus with a little more concise function than we've had in the past. The biggest problem would be that the Power option would be almost exclusively loaded with magical effects, which sorely limits its use for non-magical characters.
One solution to this would be to allow it to also handle extra 'Moves' or 'Attacks' which aren't part of the normal Hand-Controls. Things like a quick kick, using your shield to shove an opponent, or even offloading Power Attacks onto it (and in the process offering different kinds, such as a Heavy-Chop or Half-Sword-Thrust) could round it out and make the feature more useful all around.