[Scott Hebert]

If you could trade, perhaps. Unfortunately, death gems are worth 15/4 gold each (strictly speaking).

And, of course, if you're saying that you'd spend that much to get 1 death gem... wouldn't that be an argument in favor of death gems being too valuable?

And, should you wish to use a 'research unit', try the Seithkona or any other 1/1/1 mage, since that's actually better for your argument.

However, a Spectre is worth more than any 1/1/1 mage.

And finally... no, it makes absolutely no sense to use an 'above-average' unit unless you want everything to be above average, in which case I suggest you play with all magic at research level 0 and all spells costing a maximum of 5 gems.