heres my plan for my N Scale yard with a passenger termnal at a later time & engine service for diseal power. question: 1. what track through the yard should be the main line? 2. should i make the yard stubed, (if so what side) or tie in both ends whats to gain? by tieing in both ends or the up side of not to? 3. loco service set up.. should i add any tracks to or looks pretty good? 4. i have the letter A on the plan circled.. should the passenger lead run threw the loco lead (the dash lines) or should it be as i drew?? any thing else i may be missing? let me know so i can make it better. im trying for a little operation but more so main line runing. thanks!