Considering that your SPECIAL adds points to your skills' values, adding points that you didn't put into other skills should allow you to max out your stats without full Intelligence. An Intelligence of 4 gives you 15 points per level, for 20 levels that's 300 total, so you'd only need 86 points more.
Subtract the 15 from Tagging three skills and you need 386 points. Subtract the 60 points per skill from books plus bobbleheads (778 total) and you need 431 total points.
The lowest possible starting value for a skill is 7, and there are 13 skills, so in order to get them to full you'd need 1209 total points. So you already have 60 points per skill, with 15 more in your three Tag skills. There's 25 skill books for each skill (except Barter's Tales of a Junktown Jerky Vendor, which has 24), giving you, with Comprehension, 50 points per skill. It's really not that important to max out Intelligence people.
