DEGIRO to IBKR and Irish vs Us-domiciled ETF

Hi everyone,

I’m a Swiss resident and I started investing in low-cost global ETFs in 2022 with a long-term horizon of around 30 years, and the goal to keep my portofolio as simple as possible 2 max 3 ETFs.

I initially bought Vanguard FTSE All-World UCITS ETF (USD) Acc, then later switched new contributions to Invesco FTSE All-World UCITS ETF Acc because of the lower TER.

Current positions:

Vanguard FTSE All-World UCITS ETF Acc = 17k CHF
Invesco FTSE All-World UCITS ETF Acc = 61k CHF

Total = 77–78k CHF

I started with DEGIRO because it was beginner-friendly, but after learning more from Swiss personal finance resources like The Poor Swiss and Mustachian Post, I’m considering moving to IBKR.

I therefore have 2 big questions regarding certain inefficiencies i’ve noticed regarding my portfolio as i gather my knoledge on personal finance

1. Broker question: DEGIRO vs IBKR

I see three possible options:

A) Sell my positions on DEGIRO and rebuy on IBKR

B) Leave the current positions on DEGIRO and start investing only on IBKR

C)Transfer the ETFs from DEGIRO to IBKR

My doubts are:
- Is selling and rebuying worth it, or would it create unnecessary costs/spread/tax-reporting complexity?
- Is it reasonable to simply leave the existing ETFs on DEGIRO and start fresh on IBKR?
- What happens if the ETF/share class/exchange I hold on DEGIRO is not available or not tradable on IBKR?

2. ETF question: Irish UCITS vs US-domiciled ETFs
My current ETFs are Irish-domiciled UCITS accumulating ETFs.

They are simple and avoid US estate tax complications, but they suffer unrecoverable Level 1 withholding tax on US dividends inside the fund.

From what I understand, a US-domiciled ETF like VT may be more tax-efficient for Swiss investors because the US withholding tax happens at investor level and may be recoverable/creditable through W-8BEN + DA-1, depending on the individual tax situation.

So I’m considering:
A) Sell Irish UCITS ETFs and switch to a US-domiciled ETF on IBKR

B) Keep current Irish UCITS ETFs and buy US-domiciled ETFs only going forward

C) Stay with Irish UCITS ETFs for simplicity

Main questions

1. Would you sell/rebuy, transfer, or simply start investing on IBKR from now on?

2. Is it worth moving existing Irish UCITS ETFs from DEGIRO to IBKR?

3. Are US-domiciled ETFs worth the additional estate tax/admin complexity for a Swiss residents

4. what would the tax burden be on the irish ETFs positions on my curren portfolio size per annun be ?

Sorry for the long post !

Any advice, feedback, or personal experience is very welcome. I’m still learning, so there may be inefficiencies or misunderstandings in my current setup. Hopefully, discussing them openly can also serve as a useful lesson for other personal finance enthusiasts in Switzerland facing similar decisions.
Thanks in advance!