Agree with you - Seconding the Clara 2E/Paperwhite; for in-bed comfort the lighter Clara is easier to hold one-handed while the Paperwhite’s 6.8 inch screen gives you more room to use larger fonts without constant page turns. If you can stretch a bit, the Kobo Libra 2 (or a used Kindle Oasis) adds physical page-turn buttons, which are great when you’re lying on your side. Whatever you pick, set the front light as low as you can tolerate and bump the font weight up a notch to cut eye strain.
I am in desert heat and the gel suction cups do hold, damn but only if I mount on a proper adhesive disc.
Direct to the grainy dash was a no-go after a few 110 degree afternoons.
Heat wins.
In summer I push it back down once in a while and park with a sunshade so the adhesive does not soften as much.
A short arm and tighter joints help keep the wobble down when the base gets a little squishy.