Soundwise, I'm not sure CMC-8's would be an upgrade over your HLSO's.
Pricewise, it could be considered as an upgrade if you want to keep playing in the same league but be able to switch from omnis to cardioid caps.
If you want to improve the sound or your tapes and keep using omnis, you'll have to consider buying a set of Countryman B3's (4.7k modded) or DPA 4061's. But I'm not sure the price gap will be justified as those Sennheiser caps are pretty good sounding to me.
HLSx's were killer mics for their price. They both needed the 4.7k mod. But after that, they were hard to beat in their range of price IMHO.