TFSA for index fund and EE vs IBKR

Hi all

I'm new to investing, just starting out and trying to develop a plan. I'm looking to do both my tax free SA investing (TFSA) and also looking to get index fund ETFs in a taxable account.

I am looking into Easy Equity (EE) locally, as well as Interactive Broker (IBKR) for a non-us international account.

First, if I want to put my TFSA money into some index tracker ETF, do I have to use a local service like EE? Can I use IBKR? Do you recommend anything other than EE?

Second, must I buy ZAR based ETFS for TFSA? Eg with S&p500 do I buy satrix tracker, or can I buy vanguard VOO (dollar based) or similar with my TFSA money?

Third, I am worried in the long run about the US estate tax (taxed > $60000 at death on us holdings). Any suggestions on the lowest expense ratio (TER) I can get with a TFSA that is not US domeciled? South Africa providers are more expensive (aprox 0.38 ish? Vs 0.07 of some vanguard), but I can't see any other options on EE (eg VUAA, VUSD). Maybe I am just not looking for the right things, so any suggestions?

I mention S&p500 but would prob prefer some total world version (eg VT, or MCSI world etc) with a low TER. Any recommendations for this in SA?

All that being said with my current knowledge, I'd buy some SA based index tracker with the lowest TER (satrix, etc) with my TFSA (in ZAR) and set up an IBKR account for extra money to buy Irish domeciled index tracker. What do you think of that plan?