We're working with a small ISP which is connected to a Tier 1 provider. They have probably 2,000 subscribers. Recently, they've asked us to review their eBGP and iBGP configurations because they suspect it's running inefficiently. They're receiving 2+ million routes from their Tier 1 provider.
My question is, can't we just sum this into a single default route? Does receiving this 2+ million routes give us flexibility if they were to load balance between a primary and secondary Tier 1/2 provider?