Something I composed for another thread, but realised belongs more in here:
Books: The first time I read LotR, I got through The Hobbit and the entire series in 96 hours. That's four days for seven extremely verbose books (well, 6 and a throwaway). The other "flaw" in books is how minor the reward you get from them is. For clarity, I'll refer to the books that give a boost while you have them as "manuals" and the ones you have to read as "tomes".
I suggest that reading a tome should take 2 or 3 days, but you should be able to re-read it and get more out of it, with the number of times you can re-read the same book varying. Some cheaper books you only need to read once or twice to get everything out of them, other's you could read for the rest of your life and still not get everything you can from them. From some books you might get different things at different times: Perhaps reading Sun-Tzu's work the first time gives you some insight that increases you tactics, the second time leadership, the third perhaps a point in Int, and so on. In the inventory screen, books could have a "Times read" number, which would be replaced with "Book mastered" when you've learnt all you can from it. Also, if reading a tome can get a skill past 10, reading it before you reach 10 should still allow you to manually upgrade to 11. It shouldn't be a better idea to max everything out before you begin your studies.
Some manuals should require you to read them first once to "unlock" them. You have to know what's IN the reference book before it's that useful to you. Really, the difference between manuals and tomes could be blurred: there could be a manual that gives you a permanent boost the first time you read it, or a tome that after you've read it a number of times acts as a reference book.
There should also be some books on literature/novels/poetry books which should increase your reading speed, in addition to any other boosts in CHA, Trade, or Leadership. Perhaps there are some books you have to read before you can get more out of another book. Basically, books should be an intricate and complex scholarly pursuit, and a well-rounded scholar should have a REASON to keep a well-stocked library.
Lastly, you should be able to read a book without specifically needing to camp and sit down to read. While camping and resting in taverns, you could read at half-rate, and even when travelling, you should be able to get some reading done on the back of your horse, or when you stop for meals, so maybe a reading rate of 25%.