Speed Card Editing

Excel is probably the "easiest" to do that with- form the cards using cells, then have each of the cells point to the relevant information elsewhere.

For example, if on one sheet you have the value for "sunshine" in cell A1 and the value for "elves" in cell B25, and you want your "sunshine elf" value to have a value of both of those attributes added together, you'd put =A1+B25 in the appropriate cell on all your sunshine elves. If you later decide you want all elves to be worth 1 less, you just lower the value in A1.

You can do this with values, text, and to a slightly more finicky extent, with pictures. The initial setup takes some time (the same as filling in info on any set of cards, generally), but making changes would be much faster. The benefits are that it costs nothing (with Open Office), and that as long as what I said in the prior paragraph makes sense to you, there is nothing to learn.

Edit to add:
Here's a simplified example- http://truekidgames.com/AVZ_card_example.xls
I made the rows and column heights/widths add up to appropriate card size (2.5" x 3.5") and did some rudimentary formatting. If you change the names or the values in the yellow cells, all the related cells in the cards adjust.

I feel you understate the amount of learning/messing around with stuff that nandeck requires. Being so heavily script-based is a non-trivial thing. But to each his own.

There is also the magic the gathering editor if the premade templates can suit your needs. Else making your own template demands more work. Might be doable only when you have a solid game and you know you are going to release a lot of cards since it's a CCG, LCG, etc.

Else I use Inkscape. Make a template file of 9 cards, then duplicate the file and just change the text on the cards. For early prototype, it works fine. It depends on the amount of cards you need to do.

There is a way to import data from excel or a comma separated database into inDesign. You need to basically create a template and link the database to the individual parts. You can even name images in a cell and get it to link in.