Strumming vs Fingerpicking
For me its a combination. Some strumming songs are really challenging and some fingerpicking ones are challenging and then you get both the other way round sometimes easy. I also like dabbling with lead both with and without a pick, it all depends on the song, Some BB Kings blues is cool without a pick. So it often comes down to the song, sometimes the mood. Look at Neil Young songs quite a few have challenging strum patterns, interspersed with finger picking best of both worlds.