Long time member - first time poster but think I can maybe help here. I live in Godalming and up until the end of last year I used to commute daily into London. However I did it slightly earlier at 6.45-7am. The one at 6:43 always had seats available whereas the next one which was at 6:58 was a bit more hit and miss as due to being a fast service it was a bit more popular with those coming from further away. I can't really speak for after 7am but with trains at 7:18, 7:27, 7:35, 7:44 & 7:53 IIRC there's no shortage of options. Travelling home in the evening is easy with 4 trains per hour from Waterloo evenly spaced with one every 15 minutes!