I don't understand how the Magpies have "ruined it". For a start, Magpies are intelligent birds that provide great photo opportunities, especially their interaction with other Corvids. Also, outside of the breeding season, other smaller birds get used to them - they'll be alert when Magpies are around, but they won't often spook. Also, Magpies are a very effective (and noisy) early warning system, and will often see predators before other birds do.
I have the following in my small (20ft*20ft) garden:
- Chaffinches
- Goldfinches
- Blue Tits
- Great Tits
- Coal Tits (irregular)
- Sparrows
- Goldcrests (irregular)
- Crows
- Jays
- Great Spotted Wood Peckers (female and youngsters irregular - male daily for long periods)
- Magpies
- Starlings
- Collared Doves
- Wood Pigeons
- Feral Pigeons
- Blackbirds
- Robins
- Dunnocks (irregular)
- Wrens
Oh, and 6+ Squirrels (two of which breed in my shed roof) and a regular (since it was a juvenile 6+ years ago) male Sparrowhawk. Other birds turn up occasionally including a Ring-necked Parakeet, a Jackdaw, and other Sparrowhawks. So everything just gets along fine, just provide good cover and plenty of food and water (for bathing). Also consider what food to put out and where - Magpies will eat foods that the smaller birds are not interested in - some research and experimentation with various food should yield results.
I forgot to mention, the Jays take more fledglings during the breeding season than Magpies, but Magpies always seem to get the blame. I'm also wondering how many well exposed pictures of Magpies in a good setting your friend has?
(I can be a bit overprotective of Corvids, Raptors, and Pigeons, as all are much maligned - apologies if the tone of this post is a bit sharp; I'll reread it later when I'm awake properly... if I remember)