Alright I can confirm that the ICA facility escalations count as Season 1 escalations. So, without the Patient Zero campaign there are exactly 15. Meaning one has to complete every single one of them. However, with Patient Zero Campaign there are 3 additional escalations.
In that case I would recommend skipping three of the four ones below:
• Kotti Paradigm (Paris)
• Eccleston Illumination (Sapienza)
• Meiko Incarnation (Hokkaido)
• Yuuma Tenacity (Hokkaido)
If one hasn’t reached Hokkaido Mastery Level 20 you defiantly want to skip the two Hokkaido ones. Otherwise I would suggest playing the Meiko Incarnation and skip the three others.
But If one only want a new suit without much grind, may I recommend creating an IOI account? It gives one three suits for free – assuming one is okay with creating the account.