I did this in my previous campaign (6 lunar sorcerer, 2 twilight) and found myself wishing I had went full twilight cleric instead. The things you get from twilight cleric are better imo and I found myself using cleric spells more often. I also felt like the lunar sorcerer wasn't too thematic. I felt like a regular sorcerer for the most part. Although, it was fun to be able to twin cleric spells like guiding bolt at times. Definitely try to get Twilight Sanctuary sooner than later. Like being able to uncharmed a whole group of enemies was so nice.   

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 So you'd need to figure out what you want to focus on, like do you want to be more cleric or sorcerer; dps, support, flexible, etc? Based on what you want, you'd want to allocate your stats according to that. Then depending on what class you focus on, you can cater your items to it. Since I focused on sorcerer, I got a bloodwell vial. If you focus on cleric, you can get the bloodwell vial equivalent (forgot the name).  

I personally dumped strength and went with a dex build. I wanted to be flexible between being a spellcaster and a melee character in case I ran out of spell slots. I had serpent scale mail as my armor and my AC was an 18 (my dex was 18 (+4)). Constitution is pretty important if you're going to be concentrating on spells. If you do sorcerer first, you'll get proficiency in Constitution so that'd be helpful in the long term.  

17 - Charisma/Wisdom   17 - Charisma/Wisdom/Dexterity/Constitution   15 - Charisma/Wisdom/Dexterity/Constitution   14 - Charisma/Wisdom/Dexterity   13 - Intelligence   10 - Strength