I'm probably sound like a sell-out here, but I have to go with Napoleonic. There are just so many sets by so many manufacturers. Nearly every major manufacturer since the beginning has done several Napoleonic sets. There may be some questions about accuracy & suthenticity, but everybody took a shot. Every aspect was covered; infatry, cavalry, artilley, command, supply & behind the lines. It's all been touched upon at some level. I have more Napoleonic soldiers total than any other period by at least 2X. (No matter how many insignificent sets of WW2 Germans are made!)

I started collecting Napoleonics for this reason as well Bert. The history is just too dramatic and interesting to not enjoy, and its coverage in the hobby is very comprehensive. So many cool sets available, and such a variety as well. Especially with manufacturers such as Fraznap and Black Watch miniatures getting involved to add a metal option if you want. There’s almost everything you could want available. The Strelets Napoleonic sets are also very attractive in my opinion. Whoever that sculptor is, is extremely talented.

Caesar`s WW2 German range -surely the most comprehensive range ever in our hobby despite some glaring gaps.
But more seriously Strelets Crimean War range is for me among one of the best with their Boer War range not far behind. The WW1 ranges from both Strelets and HäT are also very worthwhile.
Additionally the Great Northern War Range from both Zvezda and Strelets are impressive.
And to give some kudos to Caesar their Biblical range was very good and broke new ground with their Hittites, Lybians, Hebrews etc.

Absolutely, Caesar deserves a lot of credit. They of course have wonderful sculpting and also broadened the scale by producing everything from multiple Chinese history related sets to the aforementioned ancient Kmt (Egyptians) and Incans/Tawantinsuyu, etc. Some of their historical research needs refinement (a bit too reliant on Osprey titles), but the scale is without a doubt better off thanks to their contributions.