You can compare speed of ST with CudaText.

>What IDE with plugins starts faster?

CudaText starts at the same speed as Sublime Text, but on Windows 10 it starts faster for me. Due to the faster Python DLL initing.

1. Sublime Text has the plugin 'PlainTasks' which did almost the same. Why to create almost identical new plugin for the almost the same format Todo.txt? 2. CudaText had the plugin 'Plain Tasks' which idea was doubled from the Sublime Text plugin mentioned above.

The open source CudaText has the same speed on opening huge files. It has slower rendering, but for huge files it is not the issue.