Just a few points from my prespective...
1) Anyone can do a visualzation practice. If someone told you to think of an image of Pres. Obama, his mental image will appear in your head with ease. Once you practice for a few weeks months etc the inage of the Deity will also come with ease.
2) The acctual practice takes a realitivly short time, Yoyu can do most of the Practices that I have learned in an hour or less. So if you set your alarm a bit early or do the practice right before bed many in the west can fit that into a normal life schedule.
3) Mantras can be done all day long. I do Om Mani Pedme Hung on the bus & subway, at work etc to help generate compassion and a clear mind.
4) How many of us, including me, might spend hours of time on a ball game, TV, playing with an I phone etc and then try to fit a practice around our so called busy schedule.
While Vajrayana may not be a good fit for everyone from what I have seen many of the problems that people that I know have encountered are more the result of not putting effort into making the time etc as opposed to there being a problem with learning the practice or not being able to do it. From my expeareance , the more I give up my Western lifestyle and ioncrease my Dharma practice the better my life has become. So the key for myself and the Dharma friends that I have thru my Monastery was not to fit the Dharma into the American lifestyle but to give up parts of what are considered important in the West and do more practice.
All the Best,
What Is...What Was...What Could be...What must never Be.
Something Old...Something New...Something Borrowed...Something Blue.