Unfortunately I cannot replicate your issue. I loaded a project with 2000 tests (with and without coded steps) and did not experience a form load delay when creating a "Test as Step" or a Test List.
You are correct; there is a significant delay when initially loading. It seems we both expected that for a project of this size. But the delay in the other areas is strange. Can you offer more details about your project? Are the tests sorted and structured in subfolders? Do most of your tests contain code behind files? If the file size is reasonable, can you send us the project to test? And finally, have you seen these delays on another machine running the same project or one of similiar magnitude?
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