I don't use the chapter markers myself, it took me months before I figured out what they were. Since they are (a) dependent on your book having chapters defined in a particular way and (b) too small to use in a book with a lot of chapters I just never look at it. So for me the graphic indicator is of no value at all, given the % is visible which gives me an even more precise number that mentally I would have been interpreting a graphic bar into anyway.
I posted my anti-location feelings six months ago or so here along with countless others. To those posters who are defending locations by claiming "only" new Kindle users complain - I would suggest it isn't because all users get "used to" locations, its because of recognition of the seeming futility in doing so.
What Amazon *did* thankfully eventually do with a firmware release for K3 owners at least was get location numbers out of our face, relegating them quite rightly to only visible when the Menu button is pressed. I like that approach - the minority who do have a need to see some byte number for reference purposes have access to it, and the rest of us just reading fiction for pleasure get to not see it. Unlucky for some (not that I will ever buy a touch only reader anyways) that doesn't sound like that is the case for the KT.
Personally I would be happier if they also took % off my K3 screen - great to have it available, but a distraction when there all the time. I find myself consciously calculating how many screen pages it takes to see 1% of progress - something I would never be doing if reading a paperback. Put it on the menu so at any point I do want to know I can glance at it, in the same way I would rotate a physical book to look at the spine.
No method of measuring progress is going to be foolproof given the amount of crap that gets stuffed into the back of books, be it some sort of appendices, preview of an upcoming book or whatever. So even saying I am at 90% I don't really know if the book will run to 100% or end at 91%. No solution is going to solve that beyond some sort of additional metadata/standard defining where a story starts & begins - i.e. it ain't going to happen. Hence why I would prefer seeing no progress indicators at all on screen while reading giving me an extra line of text space, with a simple button press to show me when I do want it.
As for working out whether to read to the end of the chapter/next chapter, my solution is far simpler. I just read at night until I fall asleep
. The only danger in this approach is of rolling over onto the Kindle but it has survived the last year of this approach...