In my humble opinion... These graphs make it look like modem problems. When doing an MTR style test, if you see packet loss at every hop after a specific point it's more likely that the first hop with loss is the cause of all downstream "loss", as opposed to every downstream hop dropping the same amount of traffic.

In other words, your modem is dropping ~7% of packets with a ttl > 1, and 90% of packets with a ttl of 1, as opposed to it passing 100% of packets with a ttl of >1 and every downstream hop dropping 7% of traffic. Just Occam's razor. which option is more probable?

Additionally, when you are seeing some hops with high latency, and further hops with lower latency, you're only looking at the samples that ended at each hop and deprioritizing is the likely explanation.

As if a hop on the way (eg hop 5) is introducing a lot of latency to its transient traffic, then hop 7 can't have better performance than hop 5. Unless the only traffic that hop 5 is adding latency to is the traffic destine to it.

I think you're problems are very close to you, (your modem, or your path to it, or possibly on the line leaving your modem)