You really can't afford to sneak at the end of a turn for 5, that's just too much. I'm playing melee rogue, it's still solid with the new stuff. Mostly you run behind stuff and hit them from behind, without hiding much. You have an invis you can open to get into position early on or to get out of a shitty spot. Once you start doing damage, it's alright, not nearly as strong as sneak backstab spam but that's fine since most things got nerfed anyway.
Basic build is pick dual wield to 2(absolute must), pick scoundrel at 1 and then 1 into whatever, can do 1H for damage but meh it's only 10% dmg(it's good later on though), I went with 1pt in crafting since I was gonna get it eventually. If you're planning on doing roleplay-ish rogue, 1pt in pickpocket would do fine, 1pt in leadership can also be nice. Avoid sneaking now, avoid lockpicking since it's pretty much useless(every chest has a key or can be broken).
Talents you pick backstabber obviously and then 1 of whatever. I picked Pet Pal, and you do need a char with Pet Pal for a bunch of side quests and cause it's fun, but you don't have to pick it there. Stench can be good if your rogue isn't the char you use to talk to merchants. Bully is great for damage bursts, but you need a warrior to proc some knockdowns for you(you can kd also but it's a lot harder than before to proc Bully so it's not a must anymore I'd say). Rest kinda sucks(other than 5pt scoundrel one which is solid damage since it works on stuns too).
8dex 7speed. Speed gives 1AP per turn on odd points and dex is raw damage and needed for skills and stuff, other stats aren't useful(besides maybe 1 or 2pt in con later in the game to increase max AP).
For your mage btw, you should probably start with 1 earth for the spider. In general, put 1pt in every magic school, there's a bunch of good early spells in each. No need to rush leveling specific schools, you still need the books for higher tier magic and you don't get an advantage on lower tiers other than being able to use more(and it caps novice at like 2).