Is Partitioning required in SAP HANA tables for one million records?

I think you are over thinking on a potential issue. The size of tables as you said will be rarely over one million records which does not qualify it to be considered a big table. In my application we have tables which are much bigger than that but still work pretty well over time. Also, as you said that data is mainly categorized on a daily basis so, theoretically it makes sense to partition tables on dates.  It should improve the performance to some extent. But it can also lead to good number of partitions which can backfire too from maintenance point of view.

Also auditing your records will help your cause. What I would like you to first is start with normal tables without any partitioning at the start and observer performances for all sorts of queries. If you think that the performance is lagging, then you can go ahead with partitioning till that time just observe.