If you don't already know Sonic and Robotnik's backstory in this continuity, here's the recap.

Robotnik used to be Dr Ovi Kintobor. Sonic used to look... like that. (Wait where are his ears?) Kintobor has the chaos emeralds in a machine called the ROCC (Retro-Orbital Chaos Compressor), which is supposed to transfer all the evil on the planet into the emeralds. Sounds great, right! I'm sure there's no way for evil to leak back out of the emeralds once it's all in! Anyway, the machine is unstable without the seventh emerald, so Kintobor employs Sonic to find it. As payment, Kintobor helps Sonic train to become even faster and gives him his iconic power sneakers. The sneakers are so effective that Sonic breaks the sound barrier and becomes blue. (This story is in accordance with the original Sonic Bible, and StC is the only long-running continuity to adhere to the bible!)

Things are great for Sonic and Kintobor for a while, until Kintobor picks up a rotten egg, immediately trips on a cable, and crashes into the ROCC. You know, the machine with the evil emeralds in it. Heeeere's Robotnik!

As Sonic and Omni-viewer finish telling the story in the present, Robotnik takes control of Omni-viewer to send Sonic and friends to six months in the future. The End of this issue!

Now go back to issue #7. The art is just as good there, but it didn't really strike me until now. Issue #7 was the first drawn by Richard Elson. #8 is his second. Like Nigel Kitching, Elson is one of the masters of StC. They worked together closely from here to the end of the series.

Wiki here.

Secondly, this is the first time that Porker Lewis and Johnny Lightfoot are introduced as a part of Sonic's team! Porker first appeared, and was named, in issue #1, as someone Sonic rescued. A unnamed gray rabbit appeared in #5, as someone following Sonic. Here, Tails calls out both their names as if they are important characters that will stick around a while. And that they will!

So what can we learn about them from this first appearance? Well, Johnny is eager to see something new while Porker is nervous. Tails is acting as the supportive force for both of them. Tails knows what's going on.