PSI input data requirements


I have some questions about input dataset for PSI processing.

I performed full SNAP-StamPS PSI processing chain — many thanks to STEP forum for provided tutorials and detailed answering on numerous questions on this topic.
To test the processing I used 10 images from Sentinel-1 and now would like to increase the number of input data.
Due to the snow cover the number of images per year is limited - about 10 images with 12 days time interval.
As far as I can see most research works on PSI topic include continuous datasets covering full year (or several years) period with constant time interval between images and without significant time gaps.

Could you please tell me will it be correct if the dataset for 2 years includes 20 images (only 10 per year but on the same season)?
May I use the same approach to analyze time series for 3 years or more?
Is there any recommended limit for temporal baseline between master and slave images (when using Sentinel-1 data for PSI)?

I understand that these questions are not directly connected to SNAP processing but I would really appreciate your recommendations.