i love Roon- great choice for a commander. You may want some ramp spells, like Cultivate or Kodama's Reach or, going along with Roon's ability, Wood Elves . as for the whole "magic cards cost money" dilemma, I would say you're typically better off buying single cards than buying packs. if you like the game and intend to continue playing, you'll find that the more cards you have, the less valuable packs become as you'll end up with a huge number of cards you dont need, can't trade, and can't sell. i would strongly recommend buying particular cards you know you want instead of buying multiple packs of random cards. it's a little slower in terms of growing your collection, but more effective in the long run. one example is, would you rather have 4 packs of random cards you may or may not use, or one copy of Sylvan Library , a card that is most excellent in any EDH deck playing green? Also, you may also like Glen Elendra Archmage for this deck. i think you've got this already, but Sundial of the Infinite allows you to use Roon's ability on your opponents' creatures, then end the turn in response to the "return this creature to the battlefield" triggered ability, thus permanently exiling the creature (the only catch being that you have to do this during your turn, and activate sundial on your end step when their creature would be returned to the battlefield, since you can only activate sundial on your own turn). if you're looking for things to cut to add cards, i'd suggest some of the slower cards in the deck like Mistmeadow Witch . the reasons i dont like mistmeadow are she costs 4 to activate (6 if you need to play and activate at once), she is only a 1/1 and easy to kill, and hard to deal damage with as your opponents likely have some creature they'd happily trade for her. look for other cards like her to cut that are cute or on theme, but dont really advance your game plan (reducing opponents' life totals to 0). Also, when i played this deck i included Krosan Grip Beast Within and Wickerbough Elder as ways to remove Torpor Orb because the orb really ruins your entire game when playing Roon. Krosan Grip is just a great card, as is Beast Within , and Wickerbough Elder is reusable with Roon, is a creature, and allows you to remove Torpor Orb when something like Acidic Slime will fail. Happy Blinking!

good luck with that wall of text! i do love roon though. also, Terastodon

I actually have a Sylvan Library since some of my collection is urza/4th-6th edition from when I was younger. I don't really get what's so good about it. 4 life to get a card seems steep, Or is the effect that I can put them back in any order?

I considered Wood Elves but I literally have 2 forests so it seems bad.

Glen Elendra Archmage is too pricy.

Wickerbough Elder looks interesting. I might get myself a copy because you have a point there that unless I o-ring that annoying artifact then I'm kind of boned.