Steller is better than Cardano of you like this two coin. My favorite altcoins is Tron. In CMC so many best coin exits all altcoins aren't buyable.
the TRX is a very good coin, but I would have sold it when will be pump. because I believe that the future of the TRX will be positive only for a couple of years
Tron is very speculative coin. Justin Sun has a mixed reputation. I would be very careful in investing in his projects. But this is just my opinion.