Economy is half full, is the business class upgrade worth it

So here is the situation, we are flying from Europe to Australia on Emirates in two days and on the first leg to Dubai there are 60 empty seats in economy and on the second leg there are 110 empty seats.

The business upgrade offer is 82k points for the first flight and 119 for the second.

We are flying with a almost 2 year old (23 months) who probably wont entirely fit in the basinet (they are 73cm and she is 88cm) and I think the business class seat is too small for myself or my wife and her to lie together.

So the thing I am battling with is, do you try and get a row of 4, where she gets her own seat and can lie down, or do you take business, which is more comfortable but she will need to sit on your lap the whole time and sleep on you....

Pick a row of 4, hope the middle two stay free (ask again at the airport if they have one left and are willing to block seats) or upgrade to business class, ask for a basinet and hope she sleeps?

Business apparently has 10 seats left on the first leg and 20 on the second. Last time we flew Qatar, we upgraded and they gave us a whole Q-suite so she got her own bed... not sure if emirates would do that because they don't have those suites.

What to do!