I am about 2/3rds of the way through Act 2 right now. I haven't done most of the Moonrise area quests or the Gauntlet of Shar, but I've done practically everything else on the map. My party is halfway to level 9. I'm not sure what level I should be right now, but
My custom character is a Githyanki Abjuration Wizard that I'm using as a Gish. If Bladesinger was an option, I definitely would have played that instead, but Abjuration Wizard in medium armor dual wielding magically finesse longswords is the next best thing. Haste has been extremely useful, as have a few of the magic items that increase the viability of this build. I've already gotten my Intelligence up to 20 (start out with 17, increased to 19 at level 4, ate the hag's hair to increase to 20) and have the gloves that increase your Dexterity to 18. I have a 20 for AC (22 with Haste) from Adamantine Scale Mail and the Cloak of Protection. This level I got the dual wielder feat, allowing me to dual wield the two finesse longswords in the game. My current plan for the final feat at level 12 is Medium Armor Master to increase my AC again and finally remove the stealth penalty, but that might change depending on what items I get in the future.
My standard party is Shadowheart (respecced into a Life Cleric, wielding the Blood of Lathander and Shield of Devotion, wearing +1 Plate Armor) and Astarion (Thief subclass, dual wielding magic hand crossbows with Sharpshooter, AC of ). I switch between Lae'zel and Karlach for the party's main frontline fighter. My Lae'zel is an Eldritch Knight that has a 20 for Strength, Great Weapon Master, a 19 for AC (Adamantine Splint plus the Wondrous Gloves) and the Githyanki Greatsword. My Karlach Bear Wildheart has the magical halberd that deals extra lightning damage, the Polearm Master feat, and magical half-plate. Lae'zel has been slightly less useful in combat than Karlach, but I keep using her because my character is romancing her.
Most encounters are pretty easy and I'm playing on the standard difficulty. Next game I'm definitely going to play on Tactician to see how much more difficult it is.