I'll be travelling along probably with a trailer and stuff on the bike. Theres not much to see until i hit Denver. I'm still improving my cycling ability. Right now i have a cheap giant bike. I probably will be buying somethiing like this
https://www.rei.com/product/108588/cannondale-caadx-105-bike-2017 . this trip will take place in the spring
The link doesn't work for me but I found the 2016 cannondale caadx 105. It seems a light bike for serious self supported touring. Towing a trailer certainly seems a good idea for this bike. It's mainly the wheels & tyres that I would be concerned about. Any cargo or motor adds considerable _unsuspended_ weight. Although I do some cycle touring on 32mm tyres on 15/19rims.
Electric could be cool with this bike (and mine). The alloy frame suits the smoothness. All the extra battery packs and an electric hook up can be carried in the trailer. You'll have to camp at campsites that offer electricity and charge all your battery packs overnight.
That BB30 would be a problem if you want to fit a Sick Bike Parts freewheel crank so you can have a geared human-electric hybrid. The SBP freewheel crankset fits on common threaded cartridge type bottom brackets with the old square taper or ISIS spindle, not BB30 as far as I know.
I haven't seen an example of a throttle on drop handlebars. Perhaps a thumb throttle could work, but it sounds uncomfortable to me. I always cycle tour with flat bars (some with bar ends,/aerobars) anyway so it's not a problem I've looked into.
I like 4130 cromoly frames for self supported touring bicycles. Alloy is for credit card touring, IMO, and for people who had to get a cheap alloy bike while they're building up their motored bike, haha.
Steel feels so much nicer.
Steel seems ideal for the two stroke engine, too, which you probably still have time to get to know by researching here. It might not be legal every place you are traveling through.
Steel is nice for comfort on a long distance touring bicycle and I think it would be great with electric motor, a nice smooth silent ride.
I like 26 inch wheels. I'm using 26" on the bike I am building up to motorise. Once distance goes over a certain point, the weight of cargo and the certainty of having to ride some bad surfaces means that a wider tyre does make up for its weight in reliability and comfort, IMO, even without the motor. With 26" size I could totally overspec my wheels for durability and not pay much money for them (26" is old hat now). No need to worry about the weight of really heavy duty wheels on my build as I am building a two stroke geared bike for the difficult hills and coastal headwinds.
But if you want to keep it light and simple, that could be great too. I wouldn't be brave enough to try it but who knows, it might be totally fine even to put a two stroke engine on a light alloy CX bike with a carbon fork..