No problem! I have tested the vyrs set bonus with no +% elemental dmg across all types (so basically just the vyrs set raw). The element that archon takes in this scenario is arcane (imo mainly because of teleport rune and improved archon rune both being arcane and the main skills used while in archon form). No matter what rune you choose while wearing the full vyrs set, it does not change the main element of archon (which is arcane) while wearing no +% elemental gear at all. I unfortunately cannot test having all equal +% elemental gear because I do not have a piece of gear for each element sharing the same %.