ACA reporting — when does it stop being something you can DIY in Excel?

We've been generating 1095-Cs ourselves with an Excel template + a CPA review for years. Around 180 EE now, the variable-hour calculation is getting genuinely complex.

For people who've moved this in-house tracking to a platform: was it worth the licensing cost, or did it just shift the work? And what's the risk profile of getting ACA wrong at our size — IRS audit frequency, penalty exposure, what we should actually be worried about?