The expansions to HOMM3 are wicked, but are really hard esp Shadow of Death. I keep having to restart campaigns. I don't know why but I just can't stop playing it even though it takes forever and the other guys always seem to have 50 dread knights before I've barely started. There must be some subliminal messaging in this game to keep me playing it! If Heroes 4 and 5 are as good I'm sorted for life! I will post back here when I get the new pack so I can tell you ZFR, as like you I don't want to pay for the same game again if if doesn't have the expansions, in the meantime Heroes 3 complete (original plus expansions) and Heroes 4 complete can be found on ebay if anyone's desperate.
Back soon (depending on the snail mail).