@zaffy2005 It is possible, but it is mostly reliant on the extremely low drop rate of those materials from the rematch triggers.
Ultimately, the best second tier option is a toss up since it depends on your needs. If we are talking actual end-game (ie. the final raid boss), you can "easily" get Ayer weapons for all of your characters, assuming you starting stockpiling a few things right now (they require 20 stones from said boss [and they can drop up to 9 per run ion UH], 200 Luminfragment Emels [which will come from Divide Quests, which are farmable], 50 Emerald [from disassembling 14* weapons], 100 Platinum material [from disassembling 14* weapons], 200 Excubes, and 30 Ultimate Boosters); this series of weapons has a 12% damage potential, S1, S2, S3, and S4 slots, and about 5% more PWR than a Rivalte weapon. These can also be upgraded and gain an S5, but that does require the boss' rare material.
That said, Trailblazer, Atals EX, and Rivalte can be upgraded to a potential that put them close to Ayer using 240 Luminfragment Emels; doing this with Rivalte is basically your best option if you need an S5.
However, if you don't really care that much about power creep, Novel weapons are a good general option, and they should be easy enough to get assuming we get another event that makes Rising Badge 5s more common.