I propose that when selecting and bouncing multiple External Instrument Tracks to Audio, S1 will record all the selected tracks in one playback of the song similar to the method below in S1-4. This would avoid S1 having to play the song 32 times to capture the 32 tracks.
The new External Instruments feature allows external synths and instruments to be connected to S1 just like the Internal Virtual Instruments. When converting each external instrument to Audio for mixing, S1 will bounce each track one at a time, playing the whole song each time for each track.
In Studio One 4, when we had to use separate midi and audio tracks, it was possible for me to record all 32 inputs from the Studiolive 32R mixer in one take making up to 32 tracks with just one play of the song.