Scarleteen

My current partner has something of a creampie/cum fetish (kink?). Normal protected sex with condom and pill is safe, but does not fully satisfy my partner. Would it work to use pre-cum, then put on a condom? Is there sperm or anything in pre-cum that makes it unsafe, and would it be safe with a spermicidal lube? Or what other methods of protection might work for this? Is there a best way for this situation? Or just balancing what we have already?

This really comes down to what you feel comfortable with in terms of the level of pregnancy protection the pill alone would provide you. Plenty of people do use the birth control pill as their only birth control method and feel comfortable with that, but others really only feel secure when a backup method like condoms is used too. Do you feel like you're good at taking your pill every day, on time, according to the directions?
There can be sperm in pre-cum although the amount is less than in semen so while we can't say there's no risk there, it's lower; again, this is going to be about what level of risk feels acceptable to you. I think it's fine to talk this over with your partner to see how he feels but since you're the one taking on the risk of pregnancy here, it's also fine for your comfort to be the deciding factor.

The other consideration here is that condoms are the only form of birth control that also helps protect against STI transmission. Are you and your partner both monogamous and up to date on your STI testing? If not, foregoing condoms would increase the risk of transmission if either of you have an STI, so that's something to take under consideration.