only sounds I couldn't find on splice was Rap vocals, there were some but after you look for your key and bpm there was only like 4 samples available. what I've been doing is finding most samples before I start a track, instead of deciding key and bpm before grabbing samples. then going back after my track is built up and finding flourishes and extra bits to add.
I was really jazzed to find Splice but I recently used a sound from there and another creator content claimed my video. So now even tho I use a paid version of Splice that allows for commercial work, my video - which took 7 days to produce - is making no money while the 30-day dispute is going on.