Currently, Exult defaults to a "2xSai" scaler after a new install.
For a "pixel art" type of game such as Ultima, this unfortunately has the effect of blurring the appearance of the game. It doesn't make up for the fact the original game's graphics were low resolution, and honestly looks a lot worse than the "pixelated" look.
To keep the game in the spirit of the original (and have it look a LOT better) please consider making "Point" scaling the default. Ultima 7 will be back to it's early 90's glory.
As an added bonus, please consider making the window resizable. The "2x, 3x, 4x, etc" scaling mode be automatically chosen based on the window size, making it very nice for people with high resolution displays. Either way, 3x mode might not be a bad default for modern displays.