What is the most cost effective way to lower click cost to website?
There are several combinations of "objectives" and bidding strategies.
My main objective is Volume for Desktop Traffic (non mobile) and cheap. I will mostly work with Broad Audiences, relatively untargeted.
1. Send people to website
=> Website conversions
=> clicks
2. Increase conversions
=> clicks to website
=> clicks
3. Boost post
=> post engagement
=> clicks
Can any FB ad gurus chime in and give your feedback on what combination has produced the best results for you?
I think there is no real "universal rule" here, it depends.
If you have extremely likable ads then the % of users liking/sharing/etc. will increase click to website costs if using CPC, if you have ads that get few likes but low CTRs then costs may still be high, etc.
Your ad matters as much as the targeting and the bidding mode.
Generally I would focus on 1 and 2, not 3, and go with whatever works best given the context.