I worked at Canary Wharf for four years and commuted from Highbury. Took about 40 minutes but did involve 2 changes. You get used to it.
Highbury is great for kids - village atmosphere, very safe, lots of kids clubs and pre-school groups, huge green spaces (Highbury Fields, short walk to Clissold Park which has a small zoo, both parks have great kids' playgrounds and Highbury Fields has an indoor swimming pool) north London (that means much more affordable than NW or W in most instances), just next door to trendy Islington (home to lots of celebs) with all its great boutiques and restaurants, and Highbury has the #1 and #3 best primary schools in Islington borough. Highbury is a very easy bike ride or drive into Docklands (about 30 minutes). I did it on scooter sometimes - that was fab in summer! But you have to pay for parking the other end.
We did look at moving to be on Jubilee line or DLR to make my commute easier. Considered West Hampstead / Finchley Road area (couldn't afford St John's Wood) and it's a nice area and good for kids and good transport links. We decided to focus on Greenwich - I love Greenwich! it's an amazing place and transport is so much better now it's on the DLR - but we never managed to have an offer on a property accepted so we have stayed in Highbury which was better in the long run since I changed jobs and now work in the City. However, you would find it a long treck into the West End for shopping etc. from Greenwich if that's something you want to do while you are in London.
Unless you have a huge budget and you feel you need to be in the Westminster and Kensington type location for emotional reasons (i/e/ luxury label wearing yummy mummys for neighbours) I would just forget it unless your husband will be doing a lot of travelling from Heathrow. If he has to do a lot of travelling, then a short commute to and from Heathrow can make a big difference.
Do you have some names of big London estate agents so you can check websites? E.g. Foxtons, Ludlow Thompson ...
HTH!!