Outbound Policy: Managing two very different ISPs

Sorry to ask a basic question – just looking for simple guidance.

My system has two ISPs. ISP #1 (satellite) typically runs 3-8Mbps. ISP #2 (long range MiFi) typically runs 10-30Mbps with pings running 36-38ms. However, ISP #2 seems to crater for 5-10 minutes several times per day during which throughput drops to 0-2Mpbs with pings at 600+ms – if there is even a viable connection at all. I want to set outbound policy to use ISP #2 unless it is cratering, in which case I would like to switch to ISP #1 for that period until ISP #2 returns to good performance.

First question…Is the right outbound policy setting Fastest Response Time?

Second question…In this scenario, what are the best Health Check Settings for ISP #2? Right now I am experimenting with Ping / 5-second Timeout / 20-second Interval. Does that make sense?