I think that the editing and feature requirements of producing a mere 30 minutes to show once a week is likely a problem. If you took each presenter that ever was and could allow them enough time in their area of expertise to really cover each subject or task to the level they personally felt did it in-depth justice - you would probably have the type of programme with content which would satisfy everyone. I think sometimes it must be impossible for the presenters to give what they want when everything will have to be edited down to cram as much into 30 minutes as is possible. I'll bet a lot of really good stuff which all viewers would love ends up 'on the cutting room floor' purely due to the time/editing constraints. It may be that the subject matter is whittled down in the editing choice and much of what we would love to see just doesn't get to the screen. It was maybe there at time of filming but gets chopped out to fit the number of subjects which 'have' to be covered in the programme.
It can't be much fun for the entire GW team to be restricted to a 30-minute slot. It's probably the main reason why when the presenters are given longer slots on other programmes, that we find the content more pleasing - because there's more time alloted for the presenters to really spend time on the plants and detailed gardening procedures they love to get stuck into. I suspect they are all well aware of the limitations and are likely frustrated as much as viewers that they can't just give what we all would like to see. I'm sure they would if they had the chance.
The only thing about the programme which frustrates me is when a presenter is introducing a plant and talking about it's habits, how to care for etc - but the camera quickly pans away as they are talking - and the full name of the plant is only only the screen for a few seconds. Maybe it's just me being slow - but if I'm taken with a plant a presenter is talking about - I really struggle to write down the name before it's gone from the screen. I don't have a recorder to tape the programme and I know the programme can be seen on the website for a while. But I don't always manage to do that. It's a bit like watching Chelsea on the tv - the camera pans round or focusses on one aspect of a garden and more time on the presenters talking so that you don't get a good look at the plants.
Sigh - time is money in the media and marketing and sponsorship world.
I like all of the presenters when they are given a decent amount of time to cover a subject. Sadly 30 minutes often cuts both presenters and guest garden/gardeners off just when you are really beginning to appreciate and become interested in the plants or topics they are giving you a taste of. I'm sure they'd prefer to be in a position to give more of what everyone would love to see.