I'm also looking at throwing some spare cash into the cement pit, but i think it should be cash once is willing to part with should the brown stuff hit.
Is it possible to perhaps get a rundown of the costs involved in opening and running all these bank accounts? That is now the Nedbank option. Seems like a lot of effort i.e. deposit monthly in one account, then move money to 32 day notice account, then when sufficient amount move to easy equities.
If i had to take a guess I would say that pushing your children to do their own thing would hopefully encourage them to take on more responsibility and to learn how the world really works. e.g. Missing a rent payment for month or so with your parents is not such a big deal, doing the same with rental company could put you in some hot soup.
I also use 22Seven, works great to get an overall view of what going on in your finances, but I do all my budgeting on Excel, since its way easier updating my spending or inputting variables for the month.