I haven't ran into any issue as well. You'll actually see a performance boost by migrating to SQL Server 2019. The first boost I saw were in the inserts. Our great developers have a process to import 1B+ records into a single hash table using INSERT INTO...SELECT. it usually takes 10+ hours but we cut it in half by 5+ hours.
SQL Server 2019 now allows parallel inserts (mainly raw tables without PKs and Indexes) if you specify the TABLOCK hint
INSERT INTO [ParallelInsert_Destination] WITH(TABLOCK)
SELECT * FROM [DummySource_Table]
- If the target is a heap table (a table without clustered indexes), a parallel insert execution plan is not created by the query optimizer
- Table variables do not allow parallel insert execution plans
- Database compatibility level must be 130 or above
*** Please network with me and feel free to IM if you have any more DBA questions and concerns