Davrning with a minyan is important, but it is an enhancement of davening. Saying the words is crucial, so even if you’re out of sync with the minyan, you’ll be getting the mitzvah of davening, if you want to sing the words to yourself to help focus. You can still answer amen yehei shmei rabbah, kedushah, borchu, unless you’re in the middle of shemoneh esrei. Furthermore, if you start at the same time as the minyan, many poskim hold that you are considered to have davened with a minyan even if you’re way behind or ahead of them. If given a choice between skipping words and being in a minyan, versus saying every word without a minyan, the choice is very clear – saying the words is the literal definition of davening, with only the 1st parshah of shma and the first brocho of shemoneh esrei being crucial to have in mind what the words mean. Everything else is an enhancement, important as it may be.
The overwhelming majority of conservative jews do not pray more than once a week, so it’s not an inconvenience for them to sing everything, since they’ll be out of temple afterwards, back to their car or phone or whatever else they do on shabbos r”l.
For people like yourself who want to say every word every day, three times a day, such a thing is very difficult for a lot of people who want to not spend more than 45 minutes by shacharis etc, but it is correct that sefardim sing almost everything out loud, so that would definitely be an option. If it means being able to daven properly, I’m pretty sure a Rov will tell you you’re allowed to change your nusach to sefardi, since the alternative is skipping words.