Thanks for contacting Syncfusion support.
We are suggesting you the CSG tool and the bundling concept to overcome the loading issue in ASP.MVC application.
1) CSG Tool: We can use the Custom Script Generator(CSG) tool for script file generation instead of using the “ej.web.all.min.js”. Custom Script Generator (CSG) tool to create a single file that packs together only the required scripts and CSS files together. So that you can generate the required script file for the specific controls and hence it will reduce the loading time. Please find the below references.
In the above link we have listed out how to do bundling in the CSS files likewise we can bundle the script files also.
Note: Kindly share the list of Syncfusion components used in your page that would help us to further investigation.
Please let us know if you have any queries.