Thanks. The Seurat vignette linked this paper: https://www.nature.com/articles/nmeth.4612 . Looking at Figure 5, it appears that edgeR/QLF, MAST, and voom-limma performed better than other methods after filtering out lowly-expressed genes. I am assuming from differential expression testing that if one cell-type has many more upregulated genes compared to the other cell-types, it has a higher overall level of gene expression.
I was taking a look at Seurat's differential expression testing vignette. Would it be more logical to
1) find markers by inputting 17 cell_type identities FindMarkers(my_dataset, ident.1 = "cell_type1", ident.2 = "cell_type2", ...ident.17= "cell_type17", test.use = "MAST")
OR
2) Compare one cell-type to the rest of the dataset and repeat this 17 times for all cell types? FindMarkers(my_dataset, ident.1 = "cell_type1", test.use = "MAST")