Hi
I think it really depends on what you want out of it.
Our situation is we live in a static (have done in various places since 2012) and have had our first child in June 2017. I work 2 days a week and clean 3 holiday houses (boring but lucrative) once maternity leave finishes my partner will go back 1 day a week. All in this gives us enough to live off and we save about half for the house build. We don't go anywhere or do anything off the croft but that is fine we are working towards what we really want. A business, a house and no 'work'.
To that end we are currently keep 10 ewes and 2 highlanders (who knows if these will pay for themselves in the long run). We also have a milk goat, a wether companion and a few chickens neither of which is for financial reasons (but pay for themselves in savings on cheese, eggs, milk, yogurt etc). Business wise we are establishing a market garden (80x30ft tunnel and about 1 acres outside) having previously run a similar scale profitable enterprise (slightly above minimum wage) in a different location (but similar to skye). We are also building a house, the frame will go up this summer and I will do the internal work over next winter.
I work 8 hours most days (but almost never more) and my partner looks after baba (with a few hours input from me spread across the day when she gets out and about a bit) we will share this more as the child gets older.
We love it but it is very hard work. I think the key for us (or me at least) is a fairly strict 8 hour day (dont do to much I think or burnout is on the horizon!) which, after the paid employment, gives about 35 hours a week to devote to the business and house build which seems about right based on the previous business and the spilt between summer work and winter I. E. All summer on the business all winter on the house.
Also since having the baby we have gone from 2 workers to 1 what with child care - it is totally and un relentingly full time. I think you should evaluate what you want and why. Our goal is quite clearly to not have to 'go to work', beyond maybe a day each to ensure a small steady stream of income for security and have a low impact, low cost, sustainable life. Once the house is finished we will drop our working to 1 day each to focus fully on the business. In order to achieve all this we have to seriously sacrifice many things that many people think are essential to have a reasonable standard of living - holidays, spending money, new things etc etc. On the plus side we get to do largely what we want when we want(or when the baby wants), have very low outgoings (beyond the eye watering cost of building a house), eat great healthy food and spend all day outside. It really depends what you want out of it all. It sounds like you have quite a lot on as it is at present and with a baby coming that is only going to get more. We worked out our available hours and came to the conclusion we could just about manage this - just! Assuming one of the two of you looks after the baby all the time, plus your current commitments how much time do you have left over still allowing yourselves a reasonable amount of down time, and still enjoying it? I know folk who work a lot more hours than me but is that productive and are you going to enjoy it 5 years in. Could you work less and save money by producing your own food, would you like the insecurity of that, or a small business - do you need the steady income to feel secure
H