What about Vidomina and Galtran?

In my opinion, Izra is more interesting than Vidomina.
If choosing one of the first three heroes (i.e., those who come with troops), I would prefer Galtran. The main reason: increasing the speed of skeletons, which leads to a reduction in losses (even though he raises fewer skeletons), as well as the fifth upgrade. In addition, the skeletons' stats increase. For example, under Galtran's command, level 4 skeletons on their native land have impressive stats, to say the least.
Overall, I would choose Galtran - he provides a stronger start and excellent prospects.