MileagePlus mileage accrues in one of two ways. For UA-operated flights (regardless of ticket stock) or for Premier-earning partner flights on a United-issued ticket, the earnings are strictly based upon the fare paid. You’ll get one PQP per dollar spent (excluding taxes and fees) toward Premier qualification, and you’ll get 5 MileagePlus miles per PQP as a general member (or more if you have United status).

For partner flights ticketed by partner airlines, your earnings will be calculated based upon the distance. You can use the calculator here to figure the earnings out: https://pqp.economiles.com . However, in order to do that, you’ll need to know the fare class of the flight that you’ll be booking. For the most part, the partners you’re listing do not have particularly favorable earning rates for discount economy tickets. However, most of your partner flights are (comparably) short, so I don’t think it should make much difference.

Since it seems that you have an entire itinerary planned out, I’m not sure what information you’re looking for, exactly. With the exception of the SQ flights, which might conceivably be more lucrative credited to Alaska Mileage Plan, your only option would seem to be to credit to UA. You say you want to make sure that you’re credited with “as many miles as possible,” and, all things being equal, the best way to do that is to pick more expensive flights. However, that’s not exactly recommended as a way to endear yourself to your boss or your travel department.

Finally, if you upgrade United Airlines flights out of pocket, you will get additional PQPs but, in most cases, no additional redeemable miles. If you upgrade partner flights out of pocket, you may or may not earn any extra miles; it depends upon what the partner reports back to United.