Although possible, that is extreme. Most will likely wind up in the 3 to 4 range as it is unlikely that you will be casting a spell with 2 runes and 2 techniques using Insight.
You are limited as to how many you can get to INT - 12, which means a sorcerer with an INT of 18 can have only 6. That means you will have 1 technique and 5 Runes (btw, that will also cost 6 POW). Unless you start substituting Runes on some spells, you will have a very, very limited selection.