In Report & Analytics, can I increse the number of items shown in a breakdown? If I apply a breakdown to all items in a report, as a standard it displays only 5 items per page.
If you want to do this level of customization, the preferred tool would be Adobe Report Builder.
It will allow you to do larger breakdowns and get data from multiple report suites.
In that case go for multiple reportlets in dashaboard, I don't see you have another option.
I cannot use workspace analytics for dashboards which contain reports from multiple report suites
Nops, for that either you would need to use Data extract in Report Analytics.
However, my recommendation would be to use Workspace Analytics as it provided huge flexibility on those lines.