Anything near the Disneyland Hotel will be closest to the start/finish if it follows what they did in the past.
Hotels on the corner of Ball and Walnut are usually where I look, the Holiday Inn and Suites or the Springhill Suites up there are both places I've stayed and would stay again. Not necessarily the most convenient for the parks but very close to the start/finish if they setup the races the same way. I've also stayed on Harbor and walked across to the start/finish and it's not a bad walk. Disneyland races are sooo much easier since you don't need to deal with race bus transportation. Overall, the vibe is closer to a large, well run local race.
This is the 2017 Disneyland Half (this was traditionally Labor Day weekend):
https://www.flickr.com/photos/185759646@N02/shares/356290
View attachment 691020
But also for reference the 2017 Star Wars Light Side Half (this was the race that last ran MLK weekend, was Tinkerbell before that but that race moved to Mother's Day weekend or near it):
View attachment 691029
Also, some shameless self promotion, I've been compiling runDisney maps for years if you want to see other Disneyland race maps:
https://www.magicofrunning.com/rundisneymaps