>>377568Ditch the backpack for a big seat bag or something (it's a lot more comfortable) and put some bottle cages on the frame and put some water bottles in the cages & ride 50 miles. Or try for a century, why not?
My bag (Jandd Mountain Wedge III) holds enough for day rides, & expands to hold even more (this frame does take a rack, but I don't put the rack on it unless I need panniers because... well I guess because vanity).
600 euros is cheap for a good bike!