I'm not much of a gamer, either! For my phones, I've never used anything larger than a 5 GB ext4 partition for Link2SD. So far, I've never installed more than 30-40 apps on my phones. The lower/mid range devices can only run so much before system RAM is nearly full, and the amount of CPU cycles spike up. Too much of either can slow down the device. I don't think I'll go bigger than 5-6 GB for Link2SD on my G Stylo if I decide to root it. As I said before, I don't move any data onto the ext4 SD card partition. To add to what I said earlier, I've experienced app slowdowns and crashes/freezes while doing it. If data stays internally, then the device runs like it normally should.