V1: What is the reward? Is it our salvation? Do we already have the reward then?

Does Matt 6:12 actually written that way, because Jesus is yet to die & rise again. V14-15 seems to provide a different reason. "neither will your Father forgive your trespasses". So you must forgive others first, before you will be forgiven? & how does this work with saved by faith & faith alone?

Why were the last lines added & should we change how we interpret with the added words to The Lords Prayer?

Should we feel ashamed of our prayers? If they reveal the desires of our hearts how do we balance that with praying for everything?