After a lot of back and forth and countless changes to the portfolio, I have finally found the portfolio structure that suits me best.
The whole process has now taken a year and a half and has cost me a lot in trading costs and missed returns. I can only advise anyone against constantly changing their portfolio strategy and it's best to think about it before investing your money. (Makes sense 😂)
It's also not necessarily the best idea to keep looking at other portfolios, because in my case at least, you're always thinking about changes instead of just going the way that feels best for you without looking at others.
For my part, I have now found my perfect portfolio, consisting of a single world ETF in a distributing variant (I personally have found that generating cash flow is the attractive investment strategy for me, hence the distributing one). In the long term, selected quality companies that also generate a good cash flow may be added (maximum of 8). But for the time being, I will stick with the world ETF to generate a decent investment sum.
In addition, some gold will be added to the portfolio in both physical and digital form via a savings plan and, from next year, smaller sums will also be invested in Bitcoin. I have thus found the perfect diversified portfolio for me with an investment horizon of 30-40 years.
A smaller savings plan of € 200-300 per month is running on the world ETF as well as regular one-off payments with slightly larger amounts, but here in different tranches for the time being, as the market is currently a bit too high for me

