See
https://railforums.co.uk/threads/sr-south-western-division-historical-patterns-1967-2003.220711/
This thread quite extensively discusses the service patterns of the second-generation slam-door era from the 1967 Bournemouth electrification up to 2003.
Such a pattern is something that arguably makes a lot of sense if it's possible to achieve: it gives Dorking a semi-fast service into Waterloo (which most Surrey towns of similar distance to London do have), while still serving important stops with connections (Wimbledon, Clapham Junction, Vauxhall).
I think it was 1999 when the Guildford stoppers disappeared (see the thread referred to above). But the Woking stoppers date from at least 1997, when Platform 3 did exist. So for a time (1997-99) you had the two Woking stoppers (455s) and two Guildford stoppers, one of which went to Haslemere (VEPs and CIGs) as mentioned above. The Wokings at this time were, I think (as suggested above) Vauxhall-Clapham-Wimbledon-Surbiton then all stations. The Guildford/Haslemere stoppers skipped Vauxhall, Wimbledon, Esher, Hersham, and Byfleet and New Haw.
There was also a phase earlier in the nineties (1992 to ????) when there was a 455-operated Guildford stopper (all from Surbiton) and no separate Woking stopper. And before that, dating from well back into the mists of time, a VEP and CIG-operated Guildford or Portsmouth stopper (Farnham or Portsmouth stopper from 1989-92).
I guess there are pros and cons to this. In some ways it's better to have a completely different, but still regular, pattern in the peak as it permits such things as a 30-min pattern off-peak increasing to a 20-min pattern in the peak. Insist on the off-peak pattern in the peak and you potentially end up with a less-regular peak pattern (e.g rather than an 00, 30 off-peak and 00, 20, 40 peak pattern you might end up with something like an xx47 additional in the peak on top of your 00, 30 services). The Southern suburban services of the early BR era (1950s, 1960s) seemed to be particularly good at 'alternative clockfaces' for the peak if you look at old timetables.
That said the 2004 timetable wasn't quite a complete rewrite and certainly not the first big update since 1967 - the changes of 1999 and 1989 were fairly significant updates. You still had a Weymouth service at roughly xx30 (xx35) and Poole at roughly xx00 (xx05), as per the 1999 timetable. The even-interval half-hourly fast service to Poole was introduced in 1999. The 15-min interval Portsmouth Direct was a radical update and also occurred in 1999. The Southampton-Portsmouth stopper still ran at the same time in the hour. And timings on the Exeter line had changed about quite a bit throughout the 15 years from 1989.
What is remarkable is how the 2004 timetable has remained more or less the same with only minor tweaks to this day - in the sense that the departures out of Waterloo on the main line off peak have remained completely unchanged, without even one or two minute updates to departure times. In the slam-door era, and particularly from around 1986 to 1999, times changed regularly, certainly by a few minutes.
To be fair I was referring to the mainline services, rather than suburban - I don't think these have changed at all.