I'm always trying to balance page size and functionality with the size and weight of my planners.
My system this year is my Plannerisms planner, which weighs about 325 g, and my large Moleskine notebook which weighs about 340 g. I normally don't mind carrying both together, unless I'm going to be doing a lot of walking and then it's a bit of a drag. But after years of trial and error, this seems to give me the largest page size (approx A5) in the most comprehensive system (monthly and weekly planning, goals and tracking, daily records, lists and notes) for the least weight.
Sometimes I think of trialing a personal size Filofax version of my Plannerisms layout, but my personal size Filofax with the pages in is more than 500 g. Considering I would still use my large Moleskine as my permanent archival record book, the nearly 850 g total weight would be more than I want to carry everywhere.
I also fantasize about having everything in one A5 size binder, but with all the pages in it weighs in at a hefty (and non-portable) 1040 g.
Have you ever weighed your planner? I'm curious to know how much planner weight people carry around.
And as always on Fridays, feel free to discuss anything planner-related!