Who is the stealthiest follower?
Playing a stealth thief, I find that followers (specifically Lydia) are not useful on missions.
She just keep getting us detected, so I'm forced to tell her to wait before starting a mission, which is annoying given that almost all dungeons have alternative exists that make me have to go back and get her again.
Is there a follower that would go well with a stealth character or should I not use any follower at all?
Any follower that is skilled at light armor and sneak (and optionally, archery too) should be fine. Followers should preferably be non-mage, as casting spells will attract enemies and blow your cover. Complete list of followers and their descriptions here: http://uesp.net/wiki/Skyrim:Followers
Tips to make followers extra-sneaky:
- Have them wear light armor only, as heavy armor is noisier and makes them more likely to be detected.
- Give him/her an item that has the Muffle (wearer is muffled and moves silently) effect (usually a boot or a shoe; and usually light armor too).
- Have you follower wear apparel that increases sneak skill (Fortify Sneak).
Also, note that (from the UESP wiki's "Skyim Followers - Follower Stats" article):
A follower levels up according to the PC's level up to the follower's maximum level (which varies for each). With few exceptions, each follower has a maximum level, and a specific set of primary skills, which are dictated by their class.
Prior to patch 1.6, a follower's skills, health, and other stats were set when they were first spawned (which is typically when you enter their starting cell, become a Thane, and so on) and would not increase as their level increased. Prior to the fixing of this failure of stats to update with patch 1.6, players could update a non-essential follower's stats so they would increase based on their current level by using the Wabbajack to polymorph them into another creature, after which their stats would update upon recovering their original form. Players of the PC version could also use certain console commands to fix any follower's inability to update their stats with each level.
So in most cases, leveling up the player character will also make your follower level up, increasing the follower's sneak skill (the maximum and by how much, will depend on the specific follower and their NPC class).
very good point about casters attracting attention as most of them don't have the silent casting perk
I just found out that Jenassa (the Dunmer elf hanging out at the Drunken Huntsman in Whiterun) will use only her bow if you take the Iron Dagger and Iron Sword from her. I can't remember for sure, I don't think Lydia had any weapons on her when entering your service? This may help reduce the follower running ahead of you. It seemed to work well, even when there were two bandits they came after me and she kept using the bow even at short range. Good deal for my One-Handed + Shield character who's desperate to get more skill points.