50-135 plus 60-250 is the only really challenging element.
I have tested a LOT of bags over the recent years. Here are a few suggestions:
1-Peak Design everyday backpack: superb design (the Lowepro Freeline and Photo Active are rip-offs of that design), flexible and easy to reconfigure, should hold what you wish for.
2-Lowepro Freeline (or Photo Active, for the most part they're the same). Nothing wrong with stealing a good idea. Supposed to have better shoulder straps, less modular, much cheaper. Not sure about your notebooks but the rest will fit.
3-Think Tank Urban Access : another bag strongly inspired by the Peak Design. Another take on this philosophy. Think Tank products are in general VERY well made.
4-Think Tank Perception Pro. See review here:
PentaxForums.com Error
The Shape Shifter also mentionned in the review is probably a bit large for you. The Perception and Shape Shifter use pouches, very interesting, not ideal for quick access but very flexible for extra stuff.
5-Wandrd Prvke 21 : should work for what you have in mind. Their Duo backpack might also be a good choice
6-Mission Workshop Integer : expensive, superbly rugged, should do all you ask and then some
7-Boundary Supply Errant : should tick all your boxes. Not too expensive
8-If you wish to go for a bigger, supremely modular backpack, have a look at the Peak Design travel Backpack. It can compress to 35 liters (still pretty big) but also serves as a carry-on bag, duffle, etc. I love traveling with it, better than with a rolling suitcase. See here:
Peak Design Travel Backpack Review - Introduction | PentaxForums.com Reviews
Let me know if you have more questions.