I honestly think the best commentary is with a two person team... the "smart" person, and the "idiot". You can see this type of commentary in many sports, professional poker the most. While a lot of "soul calibur veterans" hated ChaCha's commentary from EVO2K9, I thought it was great. Yes, he did go into explaining basic stuff, but thats what you need to keep things interesting, especially in a situation where the majority of people watching matches are NOT "soul calibur veterans".
You had one person who didn't really know anything about Soul Calibur, and then you had another who was explaining all the technical stuff, and why things work and don't work at a very basic level. Basically, the "idiot" was there to ask questions, and give the "smart" person a chance to explain. At the Break Weekly tournaments, this is almost what we have. MrQuotes tends to call moves and stuff as they happen (and sometimes before, he's pretty telepathic), while MarlinPie explains some of the more technical stuff.