I am often confused why some comments get downvoted. This comment is a good example.
It is not unreasonable to believe that DLC will re-work some of the game mechanics. Evidence of this can be found in Skyrim DLC, and in particular, FO3 DLC.
I will also add that FONV at the time of release, did not get the love that it gets today. FONV, like FO4, got beaten up pretty badly. Then patches, the DLC, and the JSawyer mod came out. (Along with Project Nevada and community bug fixes.)
I can completely understand where you are coming from. Here are my thoughts:
My reservation towards DLC as a solution, is just how much FO4 DLC will re-work the game. Previously, my attitude was one of, let's wait for a year of patches and the DLC, before making any judgements. Why? Because honestly, every past Bethesda game has had the same kind of criticisms at release. Morrowind was dumbed down from Daggerfall. FO3 was dumbed down from FO2. (FO3 also suffered from having a definite end of game.)
However, at this point in time, I'm not sure what a DLC could accomplish in relation to what I consider to be legitimate criticisms of FO4.
I get what Bethesda was shooting for. Something similar to what worked for BL2 and GTAV. I also understand the balance between introducing new players to the franchise, without alienating the fans of the franchise. That gamble did after all, payoff for FO3, despite the absolute howling from fans of the original classic Fallouts. (I personally enjoyed the start of FO3 so much, that I quit after reaching the vault exit... Holy fuck, that was an epic moment in gaming for me, that I immediately started the game over, just so I could experience the beginning again.)
As many have said repeatedly, Fallout 4 is a good game, but not a great game, or alternatively, Fallout 4 is a good game, but not for a Fallout game. I can't imagine what DLC could possibly add to change this.
Personally, I like role-playing games. I like shooters with RPG elements as well, but I prefer actual RPGs even more. I don't think I'm the target audience for FO4. Which is unfortunate, because I like Fallout, Fallout 2, Fallout 3, and Fallout New Vegas in particular, a whole lot.