Your computer is perfectly suited for working with audio and your audio interface, even if it is an entry-level one, is sufficient to work with the usual audio configurations.
There are 2 different issues to deal with:
1/ when you talk about “gliding notes”, I think it’s not related to the hardware but to the guitar playing technique with MG2 which requires rigor and precision to convert the played notes and not the residual sounds (harmonics, resonances, imprecise attacks).
The choice of pickups and guitar settings also come into play but to a lesser extent.
For more details, search the forum for anything related to these techniques, such as here:
Pickup Recommendations
Reduce sensitivity / ghost notes / extra notes
Tracking issues (missing/added notes)
And many more…
2/ If you can play at 128s. without audio artefacts, this is supposed to be a perfect setting for playing without latency.
But if the problem remains the same at 512s. the solution can be difficult to find as there are so many factors involved.
The most known is the optimization of Windows: I don’t encounter any problem of artifacts, latency and especially system stability, even with very busy configurations (MG2 + about twenty other plugins + audio and Midi file players + loopers, all in a host plugin including about thirty patches that can be chained through a 10 seconds morphing, etc).
To achieve this result, my computer has 3 partitions: one with Windows containing different programs (office, audio, video,…) another one with all the working files (videos, images, music, plugins, sound banks,…).
The third partition also contains a Windows installation but with only the programs necessary for audio use and nothing else. Furthermore, all applications installed with Windows are uninstalled as well as all unnecessary background services. Finally internet, firewall and antivirus are disabled (except for occasional updates).
Finally, I always give this link to download a 92-page Windows optimization guide that I apply in full each time I reinstall Windows: The Ultimate Guide to Optimize your Windows PC for the Stage
I don’t know how you use your computer and how it is configured, and you don’t have to do what I do, but by reading it and applying some tips you may solve a number of problems that cause slowdowns often due to unnecessary and redundant use of CPU or RAM cycles.
But don’t forget that the problem can come from somewhere else, the main thing is to eliminate as many causes as possible.
For example, open only one program and then gradually test with other plugins or programs, try another audio interface, etc.