Those Scott Speedster/Speedster Gravel bikes sure look nice, but i too would be concerned about max tire clearance. They come with 35c tires, but looking at the front fork photo, there doesn't seem to be much clearance for anything bigger than say.... 37c, and that may be pushing it. Granted, I am new to gravel, and have zero hands-on experience with a Scott bike (besides seeing one in my local shop). Aren't they more of a CX bike than gravel/adventure/light touring? sure, you can use any bike for any type of riding...
From your initial post: "...as well as mixing in a lot of gravel roads. However, I really want the bike to have big tire clearance, because I’d like to be able to do some trails with it as well. Preferably, I want something that can comfortably use 700x35 tires and then when need be, can handle 700x45’s or even slightly bigger MTB tires for singletrack."
I'd suggest looking for a bike that can handle up to 45/47c tires, heck even 50c would be nice for any future needs/desires, BUT run 40s for now, which would be a nice in-between for pavement and gravel. 700c and 650b ability too. Have you considered the Salsa Journeyman Sora? it runs $1,199 on their site. i was pushing that for my buddy who is currently cash-strapped. If bike riding in general adhered to him, he could always sell and upgrade later, AFTER he put in a year of saddle-time lol
It seems to me, as i've been internet-surfing for bikes for him, the best deals right now, of course with slight compromises, may be:
Salsa Journeyman Sora $1,199 (Al frame/carbon fork, 700c and 650 compatible, mech disc brakes)
or the lower-end Raleighs/Diamondbacks on sale or discount (Erik's has the 2017 Willard 1 Sora 2x9/Al-frame, carbon fork, on clearance for $699, how can you beat that for a good budget gravel bike??? Willard 2 is $899)
Jamis Renegade Expat, Explore, or Exile $879-$1,299 (Even the lower Exile has room for FIVE water bottles, YAY!) Heck, a google search can find you a 2017 Renegade Exile for $700!
Giant ToughRoad models, but they're only 2x7, 2x8, and 2x9
A step up could be:
Salsa Vaya 105 $1,999 (Steel frame/carbon fork/700c at 50c wide tires)
Kona Rove NRB $1,799 (Al frame/carbon fork, 700c and 650 compatible, mech disc brakes but 1x)
Kona Rove ST (all steel, 700c and 650 compatible, but 1x)
SO MANY choices these days. let us know what you decide upon and how it rides.
eric/fresno, ca.