Fallout 4 needs to make skill points worth something. Being able to max out all skills is incredibly bad design that negates any choice the player could possibly make.
the best system would be one where skills max out at 200 (but can go up to 250 thank to perk and equipment bonuses) and you can tag only 4 skills, your tagged skills are immediately increased by 20 points and evolve faster (due to having their caps raised by 50%).
a cap of 200/ 250 is neccesary in order to make maxing all skills completely impossible, also skill books should be completely overhauled, by they would increase their respective skill when the player levels up, the maximum skill bonus you could obtain from books each level would depend on your intelligence and perks, as well as wether or not the skill increased by it's respecive book is tagged.
another, unrelated suggestion:as for followers, it should be possible to "make your own", by purchasing slaves for example, whos appearance, S.P.E.C.I.A.L, tagged skills and karma are completely customizeable, these followers could also be "trained" to further increase thier skills and unlock perks which would make them more powerfull. however restrictions would need to be imposed to prevent them from becoming overpowered, one thing would be to make them of a lower level than the player, their base level would be that of the player divied by 4, and they would only gain a third of the XP the player does.
"regular", pre-set followers would also exist, the difference here is that any characters you can befreiend can be recruited as followers.
all followers would have special "perks" based on their skills and attributes, for example a follower who has 5 or more INT and a security skill of 40 or more could attempt to hack terminals for the player, a follower with 5 or more AGI and a "small" body type could climb through certain spaces and open doors from behind for you, etc...
all followers can have only 2 abilities, and in the case of personalised ones you can choose the ones you want, as long as they meet the criteria.