Watch the episode of Friends where Monica makes a foreskin for Joey so he can audition for a movie requiring an european actor. I think she uses salami to simulate it.
What the fuck? That actually happened?
I'm uncut but wish I had less sensitivity..lol!! After cumming just touching it or trying to immediately go for round two is impossible coz it'll be that sensitive...So maybe your decreased sensitivity is a blessing!..haha
Most guys would find it impossible to remain sexually active right after orgasm. There is a period know as the refractory period whose length differs from man to man. Some, rare, men may be able to engage in sex more or less straight away, but most would need an hour, maybe even more. I think it tends to get longer and longer as you grow older.
I don't believe that the refractory period is determined by sensitivity, you'll just feel less stimulation during sex if you are less sensitive.
OP: The senslip or manhood may be ideal for what you seem to desire. Bare in mind that as your glans grows used to being protected it may be difficult to go back to being exposed quickly. The effect will probably be gradual in both cases as your glans grows accustomed to each state.
If the glans is left exposed it will always adapt to its state by lowering its reaction to external stimuli and by growing keratin.