Hi Phantom,
1. Virtual fullscreen should be the default. If it doesn't work, press ALT-Enter.
2. Here is how to change the UI size.
You also change to a specific scale in the settings file. We may add it to the options screen later. Look for:
"dpi.auto_scale_dpi_to_fit_display": true,
"dpi.auto_scale_dpi_minimum_display_size": [1920, 1080],
"dpi.reset_to_pick_best_dpi_scale_factor": false,
"dpi.dpi_scale_factor": 0.750,
in C:\Users\Blair\AppData\Local\sins2\settings\settings.json and change how you see fit.