Hi Wismie,
I would recommand targetting a global allocation for all your (liquid) assets, including taxable, pillar 2 and 3a. Since pillar 2 allows to add some tax efficiency into the mix (depending on your taxable regime, which should be checked), @Dr.PI’s splitting the world topic might contain relevant approaches to the situation: Splitting the world
Edit: I may have misunderstood the question, which may be “should I keep assets with high growth in my pillar 2 account since it won’t get taxed until I withdraw them?”, in which case, I would say the answer depends on the capital gains tax regime under which you are and will be at the time of pillar 2 withdrawal. If you are facing low or no capital gains, then favoring assets that pay income (divindends or interests) in pillar 2 probably makes more sense, irrelevant of the total growth of the account, since capital gains will get taxed (at a preferential rate) once you withdraw your pillar 2.