So, I finished Fallout 4.
All my initial assessments still stand. It itsn't leaps and bounds different from Fallout 3 in terms of gameplay but, clearly despite Bethesda's best efforts, the Commonwealth isn't nearly as compelling as the Capital Wasteland or New Vegas.
The storyline is pretty ambitious, but ultimately empty ( Does anyone playing this game actually even care if they have a son? ) and the elevation through any and all of the factions is super-duper forced. You can pretty much become the boss of any of them by doing a handful of missions over a couple of days.
The central philosophies of the different factions that ultimately put them in conflict, is interesting, but it isn't taken nearly as far as it could have been, and I ended up Destroying the institute but leaving the other three factions to continue on. That ending seems to be pretty buggy though - as certain quests for the Brotherhood seem frozen and dialogue from the Railroad doesn't match with what happened.
That's probably the games biggest problem really - it's almost two years on from release and this game is buggy as all hell. Shit gets frozen, quests don't mesh-up and items and characters are easily knocked from their pathfinding routines. It's annoying, and did I mention it's almost two years from release? How does this stuff not get addressed at all?
It's old code, and the interface is super clunky. Bethesda need to spend lest time creating assets for their world and more time actually making the experience of visiting that world seamless and intuitive. The game is fine, and there's fun to be had here improving your character and using the VATS system - but it's a game that plays like an artifact of old-school thinking, rather than something new and interesting.