I think you may be putting more focus on time to bedding a woman than it deserves. Likely because you have stumbled upon the importance of moving fast to increase your chance of getting the initial lay.
Intensity and frequency of orgasm tend be the big determinants of where they place a man sexually, in my experience, and its these characteristics that seem to provoke the "Marry me please" scenario. Furthermore, again from what I have seen with the women in my life, is that the quickest lays they have had are often emotionally destructive rebound or revenge fucks sparked by the ending/turbulence of serious relationships. But these sexual encounters often "don't count" (whatever the fuck that means) so maybe they don't occupy mental space in the same way?