What is the significance of the final few ragas in the dashavatara ragamalika?

[P. S.]

In Muttuswami Dikshita's dashavatara ragamalika, the ragas are as follows
Matsya - Natta
Kurma - Gowla
Varaha - Sri
Narasimha - Arabi
Vamana - Varali
Parashurama - Kedara
Ramachandra - Vasanta
Balarama - Surati
Krishna - Sowrashtra
Kaliyuga Venkateshwara - Madhyamavati

Natta, Gowla, Sri, Arabi and Varali are the Ghanaragas. I have heard of a set of secondary ghana ragas - are Kedara, Vasanta, Surati, Sowrashtra, and Madhyamavati considered the secondary ghana ragas, or are they ragas with little association apart from being in the same kriti?

[kmrasika]

@P. S.
Just my two cents until the experts jump in:
They are all maṅgaḷakara rāga-s (ushering auspiciousness) that can be rendered at any time of the day.
rāma has a unique connection with vasanta r̥tu, the season in which the avatāra takes place, so very apt.