In regards to an optimal staggered withdrawal upon retirement, you are supposed to spread your pillar 3a contributions over multiple portfolios to allow for more control over the impact the taxation will have. VIAC, for example, offers max. five virtual portfolios to do that.
After what initial deposit to these five portfolios should I consider moving on to another provider and start filling up new portfolios there? If there are no annual fees other than a fairly identical TER, I don’t see why I should stick with “only” five portfolios and not have my pillar 3a essentially spread over an infinite amount of portfolios from different providers? Or am I overthinking this?