So we start with 28 Special stat points.
We know the Institute has cyberware so say at least 7 more Special stat points.
We have the Special Bobble heads which is 7 more Special stat points.
So total of 42 Special Stat points out of 70 before any perks are spent on it.
That is an average Special Stat of six.
I think we get 3 perks to spend as tag skills (some of the SS have been level one but had 31 points of Special stats).
We also have the Skill Bobble Heads which is 13 more perk points.
We have 100 Books each providing a perk.
Lets say on an average play through we will get all of the Bobble Heads and 2/3 thirds of the books.
That is 67 of the books with 3 tags and 13 skill perk Bobble Heads, we have a total of 83.
Say the soft cap is 50 before we add in any DLC so 49 perk points.
That is a total of 132 perk points out of 275.
That is not counting any quest related perks it might be possible to earn.
Give that some of the skill perks are kinda of mandatory and there will be some overlap, I'd say it would take at least 3 play throughs to try everything out.
Add in roleplaying, different play styles, variations due to the order the perks are taken, and male/female SS, and you have a lot of play throughs to look forward to.