you could make some changes to get less vampire drain on the battery as well...
1 turning off cabin overheat protection
2 Always Connected' must be turned off.
3 Energy Savings' must be turned on.
as far as long term usage, charge to what you need on a daily basis however less charge will equal more lifespan as you have read. Charging to around 70% will give you much more lifespan vs 90 but if you really need to use more then 70% of your battery then charge more. Also if you use less then you could charge less on a daily basis. Personally I charge to 60% daily but if I know I need to travel further tomorrow ill set my car to charge more tonight to be prepared.
Heres a chart showing a general example of how charge percentage of a lithium ion battery relates to they number of cycles you get. These aren't exact numbers for a Tesla but it gives you an idea of how reducing your daily charge limit can increase the cycle count.