Definitely viable given that there are four adults in the household, some of whom would be around for much of the time. (You've said your daughter would never be left alone - that isn't necessary so long as she's safe to be left on her own sometimes, which most 11 year olds are. The main thing is to ensure she isn't isolated, bored, and lonely, which would have been a significant risk if you'd been planning to leave her alone all day every day. I'm relieved to see that isn't the case.)
The academics are easier than most people think, as it is more efficient than at school, and doesn't have to be done 9-3 M-F. So you and her dad can be involved with that during the hours you aren't working.
You needn't worry about it just yet, but be aware there is a significant amount of facilitation needed if she does GCSEs while being home educated. In part, that is because there's just so much more choice than at school: which particular IGCSE English exam suits her best? Should she sit it at 15 or 16 or 17? Spring or autumn? How will she prepare for it: local tutor (which tutor?), online school (which one?), local home ed study group, college, independent learning? And you need to identify a local exam centre which will take her, and make sure she's properly entered for it. Multiply that by all the subjects. So many decisions!
That isn't likely to be a deal-breaker. Other local parents and people on national HE Facebook groups are very helpful. By the time your daughter is working toward exams you will have a better understanding of what's involved. Just a warning that one or more adults in the family will need to do quite a bit of admin and research at that stage.
For the next few years, however, facilitating home ed won't be a vast amount of work. There are many options for how to do it, but you can just figure it out as you go along. Unlike in a school classroom, it's easy to adapt and it's no disaster if the approach you try first doesn't work out.