I have 3 kids under 5 and am now getting the monthly kid money. Trying to figure out my strategy. We dont NEED the money so I'd like to invest it or allocate it for later spending (college, mission, wedding, etc)

I'm currently debating between 4 options:
1. 529 - From what I can tell, 529s are a solid option to save for college expenses with some tax breaks but you cant pick your investments. Utah's vanguard age-based funds are effective but I wonder if i'm leaving money on the table compared to traditional vanguard ETF.
2. ETF - As stated above, putting money in VTI or VUG could potentially make more money than the 529 but then you end up paying income taxes on it.
3. Roth IRA - As we've been saving for a house, we have not opened an IRA yet. Some websites say to not put money in 529s until youre already maxing out your IRA. Once we buy a house, we will definitely open up the IRA and max it out.
4. House - Along the same lines as #3, we already have a 10% down payment already saved but we haven't bought a house yet because of the crazy market and unsure location stuff. Should we continue to save money for a higher down payment?

Let me hear your advice