Dear @veskuh,
one issue I see, that the Issues and Merge Requests usually will not be migrated.
Hence it would make sense to either take care open issues and MRs at git.sailfishos.org (some of which are open for long) before migrating these source repos or to also migrate them to Github (which will need some scripts to perform this; AFAIK such scripts do not publicly exist, yet).
For an example, see https://git.sailfishos.org/mer-core/udisks2
P.S.: Before starting the next hosting migration, it IMO does make sense to finish the last one, first: I have not seen any action (but maybe I missed something) towards migrating the content at together.jolla.com (“TJC”) to forum.sailfishos.org (“FSO”), as announced / promised by Jolla multiple times.
Can you please point out the status of that migration.