Searching and Model editing experience is too slow

In a big AAS live connect model - as well as a small mashup model, Searching the field list, adding a custom measure, changing datatypes etc are all painfully slow interrupting designing flow. They should be instant and asynchronous to maintain a responsive user experience.

It has been really bad for a long time and I'm surprised it is continued to be accepted by the design team.. this is the sort of thing that frustrates users more than anything else and can create bad feeling so much to easily kill a product.

Please make the UI more responsive