Mods? Absolutely!

http://skyrim.nexusmods.com/mods/9286/? does an amazing job of rebalancing the game and adds some great perks for the stealthy archer. Not only is the Marksman tree expanded, you can use your Alchemy skill to create explosive arrows.

The Sneak tree expands to include "Sneak Tools" perks. They allow you to craft arrows with ropes. Use them to scale walls and cliff faces. And make distraction arrows to help draw an enemy into the open.

If you do Enchanting, Alchemy, and Smithing you might as well not really call them an Archer.

That would be a Master Craftsman build and you don't have to invest too much into either armor or weapon perks, just a few initials to get the base bonuses. Obviously you can be an archer, but when you focus on all 3 crafting trees, imo that's not really any type of combat speciality build, that is a crafting build. You'll easily become OP with archery if you invest heavily into it as well. Might as well take some speech perks and make lots of gold off of anything extra you craft (which you will have a lot of since you're planning on going to 100 with all 3 crafting perk trees).

I can't help you with mods on here. PC mods only allowed and I don't play Skyrim on PC.

I agree, use the sneak skill. Undetected, you're talking about one shot one hit kills with a bow.

Archery is your close combat weapon.

Especially with that many crafting skills there will be no need for a dagger.

I have a no sneak archer that has never used a melee weapon yet at level 35 with just smithing up to Orcish armor and alchemy.

I do lay down a fire rune in front of me before a fight just in case anything gets close,often times I don't really need it though.

Enchanting Alchemy and Smithing all at the same time.... yay boring I guess. My archer, went with Enchanting. Still actually haven't enchanted anything, is the funny part. Using a Superior Glass Bow at level 32, and I can kill a dragon with 9 Dwarven Arrows: Archery skill is 64. Archery perks yes. You will cry if you choose the 2nd rank of the perk that slows time... so be warned!

Yeah I never felt the need to get that perk it seems a bit overkill to me.

Actually my current archer hasn't even got the first slow time perk yet at archery level of 97,I've got everything else though except the master perk.

For me the first perk slows time more than enough,no need to go any further with it.

That's how I view a real archer.

I have a Master Craftsman build and by not taking any combat perks and investing all into what you create, it balances itself out to be just about the same.

The second rank of the perk, slows time too much for my taste. It's a huge Stamina Drain. My archer is magic-based, so only a couple investments have been made to Stamina. Everything else gets pumped into Magicka, some Health. The first rank is just right.

1. I do have to echo what previous posters have said: don't do all three crafts. "Artificer" builds can be nifty once in a while, but they become a snooze when you set them up. If you want to go that way and become OP, though, I'll add a flexible (and reasonably complete) build later.*

2. You won't really need melee, especially if you work in shouts (Unrelenting Force, Whirlwind Sprint, Ice Form, and (DB) Frost Breath.**) If you feel safer with a melee weapon, go light armour with sword-and-board. You can also go heavy armour, though it will affect your stealth without other tricks. The ideal shields would be either Spellbreaker, Targe of the Blooded, or especially (DG) Aetherial Shield. (DG) Auriel's Shield also works, but it's better for melee builds.

3. Conjuration doesn't hurt - the Bound Bow is quite strong without crafting, and summoned allies keep your options (and range) open.

*This is a reasonably complete, flexible build if you just want to be OP:

**In Dragonborn, there is a buff that allows Frost Breath to also put Ice Form on the target.