At 1411 kilobytes per second, a 1 minute, 26 second .WAV file is 14.5 megabytes.

If you apply the .WAV sample to an .S3M file, its size should be just above 14.6 megabytes, regardless of how many times it's played.

Shrinking the size of the .WAV file would probably necessitate adjusting to a lower bit rate - what that means in terms of relative audio quality is practically meaningless until you get to about the bitrate of an .MP3 file.

In other words, .MP3 files are smaller because the bitrate is compressed to a maximum of 320 kbps.

The point of discussion becomes at what point is it noteworthy to compress an audio file? For a 1-second sample, leaving it in .WAV is fine - that will work for module music.

For a 5-minute sample, converting it to .OGG saves disc space - it has higher audio quality, but can't be read by most pre-modernist module trackers.

For general tracking, I suggest using Renoise - you can't apply the instrumental effects that you can in OpenMPT, but you can use a wider range of audio sample formats.

I don't have experience in other trackers, but Renoise uses a modified version of OpenMPT.