I'm sure the answer is no, but is there any official ruling on mixing different colored protective or artwork design sleeves within my deck; i.e., one color scheme for heroes, one color scheme for neutral, and one for villains? And if the tournament ruling is no, how about when playing a friendly game at a LGS? Are opponents going to have a problem with this if I do so?

The character cards and battlefield are required to be different for official events.

If you are talking about having two different sleeve designs in the same deck, that's not gonna be ok. That's a marked card. Even if you aren't actively using it for an advantage, it's not gonna go well if you are playing folks that you don't know really well.

All cards in a deck must have sleeve of the same color.

Card Sleeves Players are required to sleeve their deck in opaque card sleeves for Formal and Premier events. All sleeves within a single deck must be identical in size, color, texture, and condition. At Relaxed events, if a player is not using opaque card sleeves, he or she must make sure that all card backs in their deck have a uniform appearance. Players may sleeve their characters and battlefield, but they must use different sleeves from their deck. Players should bring a few spare sleeves for their deck in case a card sleeve breaks or becomes unusable during a tournament.

I would personally have a problem with it because it is giving you information about what cards you're about to draw. Just like if the cards were marked.

I'm sure the answer is no, but is there any official ruling on mixing different colored protective or artwork design sleeves within my deck; i.e., one color scheme for heroes, one color scheme for neutral, and one for villains? And if the tournament ruling is no, how about when playing a friendly game at a LGS? Are opponents going to have a problem with this if I do so?

Why would you possibly want to have different card sleeves within the same deck? You're basically asking if it's ok to mark cards. The answer is a resounding NO. The backs of your cards, whether sleeved or unsleeved, need to be identical.

I have First Order artwork for Villain characters.

New Hope Leia (RIP) artwork for Hero characters.

Originally I was gonna have different colors for Hero/Villain cards but then I remembered that Neutrals can be used in both and it's hard to get 4x Thermal Detonators (along with a pain in re-sleeving every time I switch) so I went with all Purple for all my other cards.

I'm using straight black UltraPro for both Heroes and Villians decks so the cards can be easily swapped around if needed. I'll eventually figure out a sleeve type for characters.

I missed that bit about Characters and Battlefield having to be different from the rest of the deck. A good idea anyway to help avoid mixing them up, but hadn't realized tournament rules were requiring them to be different.

You're not actually required to sleeve your characters and battleground; the rules say you may, but if you do, they have to be a different color.

While it is not required to use opaque sleeves, it is highly recommended, especially since any alternate art cards are printed at FFG and the color will be slightly different than the other cards in the deck. This will come into play as soon as the First Order Tie Fighter alt art cards start making their way into people's decks.

CARD SLEEVES (Page 4):
Players are required to sleeve their deck in opaque card sleeves for Formal and Premier events. All sleeves within a single deck must be identical in size, color, texture, and condition. At Relaxed events, if a player is not using opaque card sleeves, he or she must make sure that all card backs in their deck have a uniform appearance. Players may sleeve their characters and battlefield, but they must use different sleeves from their deck. Players should bring a few spare sleeves for their deck in case a card sleeve breaks or becomes unusable during a tournament.

You're not actually required to sleeve your characters and battleground; the rules say you may, but if you do, they have to be a different color.

Which seems silly to me, I haven't figured out the reason for that yet...

I find it strange that you can't have tranperent sleeves, FFG makes tranperent sleeves and now you can't use them :-/

The card backs are likely to be inconsistent as the Alt Art Cards in particular use a different printing process.

I find it strange that you can't have tranperent sleeves, FFG makes tranperent sleeves and now you can't use them :-/

It's not all that strange. It's to keep you from knowing what cards your going to draw. If your card backs are 100% pristine, you'd have marked cards in your deck and would be able to see them.

Plus the promo card backs are slightly different than the rest of the cards, making them marked cards.

I find it strange that you can't have tranperent sleeves, FFG makes tranperent sleeves and now you can't use them :-/

It's not all that strange. It's to keep you from knowing what cards your going to draw. If your card backs are 100% pristine, you'd have marked cards in your deck and would be able to see them.

Plus the promo card backs are slightly different than the rest of the cards, making them marked cards.

I think the fact that FFG uses different production methods with inconsistent results (in house versus not in house) is what is causing opaque sleeves to be required. Marking cards is cheating and marking a card back is about as easy as marking a sleeve back. Requiring opaque sleeves doesn't stop that.

I find it strange that you can't have tranperent sleeves, FFG makes tranperent sleeves and now you can't use them :-/

It's not all that strange. It's to keep you from knowing what cards your going to draw. If your card backs are 100% pristine, you'd have marked cards in your deck and would be able to see them.

Plus the promo card backs are slightly different than the rest of the cards, making them marked cards.

I think the fact that FFG uses different production methods with inconsistent results (in house versus not in house) is what is causing opaque sleeves to be required. Marking cards is cheating and marking a card back is about as easy as marking a sleeve back. Requiring opaque sleeves doesn't stop that.

I'm not talking about intentionally marking cards of course that's cheating. Cards get dings and nicks all the time just from being handled. Using opaque sleeves definitely help with that, because if your cards are dinged up a little and you are using clear sleeves, they are marked and you can't do anything about it, short of replacing the card.

I've always just used opaque sleeves and of course those can get dinged up and marked just from general use too. It's best to change them out every so often. For small local, relaxed events no big deal, but anything above that, new sleeves.

Best part about only having 30 cards is a pack of 100 Dragon Shields will last you through 3 switch outs, if you need them.