I disliked both. Radovid is a spoilt and angry child asserting himself against a world he doesn't really understand. He was mistaken in siding with the Order and Salamandra ~ and only averted chaos and disaster because of the intervention of Geralt and the Sorceresses, with Foltest's Garrison.
His hatred of Phillippa is understandable ~ but his decisions at Loc Muinne were just as misguided as those prior to The Witcher.
As for Phillippa ~ she manipulated and bullied her way into trouble ~ forgetting that an advisor's role is to advise rather than manipulate, or 'remove'. Assassination of Kings was never going to go down well, and secrets have a habit of coming out into the open.
In my opinion both are evil in different ways, both will have caused great damage to the world they live in. I find the Order to be more problematic overall though, so if push came to shove and I had to choose one to hinder more than the other I would side against the Order and Radovid. I don't like fanatics who believe they have the right to dictate the lives of others for their own gain, especially when a political tool, in the hands of an overgrown child.
Some have criticised Triss for "falsely" accusing Sile of being complicit in the assassination of both Demavend and Foltest, but I think this accusation is appropriate. She (and the other sorceresses of the Lodge, less Triss) set Letho to kill Demavend, making Conspiracy to Kill a given. The methods she used included providing tools, access to allies and travel methods that made Foltest possible to reach - her provided allies the Scoi'atel, provided the transportation used to escape from the city of the La Valletes, and shelter in the Forests of Flotsam, as well as additional forces to move the other members to Vergen where they attempted to eliminate Henselt.
This would be sufficient to make them accessories to murder, and attempted murder, although not in this case of conspiracy. Triss makes the connection between the three Kings, the Kingslayers and the tools used/provided by the Lodge, and concludes that both Foltest and Demavend fitted what she knew of the plan. I do fault her for not *mentioning* this possible complication when meeting Sile in Flotsam, although she didn't get a chance to check her suspicions before being forcibly removed by Letho.