Hallo Andrew - good to see you again, and to read about your continued work in the area of the relief funds. I believe you're correct - she was initially given an allowance of 2 pound a week. Stormer has written that in 1927 the Relief Fund reviewed her payments, and although they decided on that occasion not to stop the payments this decision was reversed in 1929.
Ada does indeed seem to have been an independent, intelligent woman - she may have been a first wave feminist, although there is not enough data extant on her political or philosophical beliefs to draw such conclusions, and we can only deduce certain possibilities. She came from one of the more progressive political milieus for woman at that time - New Zealand lead the world in granting women's suffrage in 1893. I find it interesting that she seems to have had a rapport with William's sister, Margaret ("Peg"). Peg was rather a bluestocking - she was a comparatively early graduate of Edinburgh University, which had started admitting female students in 1892.
We do need to keep in mind that there is a paucity of direct evidence regarding William and Ada - there is a terrible temptation to fill the gaps with inference, and while speculation as to their characters and relationship is interesting, we do need to keep in mind that some of the speculation is rather tenuous.
Take, for instance, the idea that Murdoch was unusually progressive in having a wife who continued to work after their marriage. If she did indeed do so, it would possibly be an interesting insight into their characters. Even as late as the 20s, when more career options were open to women, it was often considered unusual for women to keep working after marriage. Grace Lager, for example, uses the example of her grandmother having to conceal her marriage so she could continue to teach in her feminist study Posing a Threat: Flappers, Chorus Girls, and Other Brazen Performers of the American 1920s (the gig was up when she became pregnant with their first child).
However, it has not yet been established whether Ada Murdoch did continue to teach - this seems to be a rather vague oral tradition. The last I heard, Murdoch researchers were still attempting to establish whether there was any record of her teaching during her marriage - so far, they had found no documentary evidence to collaborate the story. Hopefully something has turned up recently, but I haven't heard of that happening.