I highly doubt Arc the Lad Collection will be worth much even in 10 years. There is just not that much demand for this game. Have you checked eBay for latest going rate? It is not even getting the MSRP for sealed auctions.
Another question you can ask yourself is, "Are you ever going to actually sell it?"
For me the answer is easy, no. I can't bring myself to sell any of my games. I pick and choose them wisely and therefore don't have that many.
For example, I just recently opened my sealed Nintendo 64 Majora's Mask (Gold), Ocarina of Time (Gold), Donkey Kong 64 (w/ Expansion Pack), Diddy Kong Racing, Pilot Wings, Blast Corps, and Cruis n USA. As well as sealed Zelda Oracle of Ages and Seasons. Why? To play of course! I never plan on selling them anyway.
Also, I am still looking for a Earthbound 64. If I find one, I am opening it to play.
Chris