Sections - Blank spaces and stacking?

i’m unsure if i’m just being stupid or if its just not there as functionality yet. But with these new sections is it not possible to have uneven sides? I.e. 2 tiles on the left but 3 tiles on the right. For example here it only seems possible to add the next tile to the left?

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You also dont seem to be able to force where sections will stay? I.e. on mobile id want 2 sections next to each other rather than them all just being in a single column