I'm kinda new to intermediate, but already have a few opinions on the matter

At a first glance, bo1 + "one restart" seems similar to a normal bo3, regarding to reducing luck-factor at least. But it makes a bigger difference in the gameplay. In bo3 games you (somewhat) get to know your opponent. His skills, style, worm order (!), so you can adapt.
Manual placement seems to be the best solution against luck, but IMO, it would kinda turn intermediate into "elite light", with less improvisation and human factor. (Next step is edited maps...

)
I think this scheme is a gentlemen's game, for people who got time and who care to know their opponents as human beings too.
Summing it up: intermediate is intermediate and it's bo3 (or more).
I say let's keep bo3 as default, any other solutions
only if both agree, as franz suggested as well.
Edit: a few suggestion could be useful, regarding the maps. If you play on "island", avoid girder bridges close to the top and long slopes ending in a big plophole. When playing on a cave map, watch out for thin ground at the base. Also if playing bo3, the first two maps should be the same style (island or cave), so both players will go first in similar conditions.