Third party solutions like CloudFlare are good but may be prohibitively expensive, we still have to analyze those in-depth.
I do not believe this is true. The most expensive Cloudflare tier is $5000/mo. It is peanuts compared to the other infrastructure cost to run BP.
At scale, the cost of Cloudflare's enterprise tier services may not be tremendous compared to server costs, but 5,000 USD/month is quite significant for a testing phase.