I don't think you can compare evony promo's with tynon or any other ucool game, its been around for almost 5 to 6 years now and is probably brings them the most cash.
unlike tynon there is no ceiling nor caps to worry over stunting players growth. albeit its over run by neat and horrifying lag and of the like; but that won't stop the cash flow.

Ironically i'd bet dave reads these forums more than people think; he and the rest of ucool don't respond, why would they; so many complain here about things but still fork over the cash in the end; only when the overhead starts to catch up and it costs more to run it then they make, will they make something happen in my opinion.
could be totally wrong, just what i think.