Which one of these would you pick for your vanilla Swarm strategy?
Kobolds are well-established for obstructing parts of the map as well as providing a high damage rate once they become numerous.
Reanimates propose an interesting alternative to Kobolds, with basically much better durability at the price (although only slightly) of mobility.
The number of figures cannot really be compared, Kobolds starting with three but growing as time goes by (if allowed by the heroes), Reanimates starting with their full group.
Obviously both monster types have different traits so not every quest would allow both.
Ignoring Blast effects for the sake of the discussion