Angus as far as nerdiness/flow is concerned . I especially like Hugh Stanley, which gives you different numbers of syllables in each name. My second choice would be Cormac. Each of those has the same Celtic spunk of Angus, but doesn't present you with flow/nerdiness issues. Ewan and Eamonn, whilst lovely names, sound more try-hard to me.
I'm due in August and I've had Angus on my list for years. I think Angus Stanley works but I really like Ewan Stanley, if you want to keep the Stanley. I had originally chosen Aengus Andrew for my baby but I changed it to Aengus Gunn because it had more family connection - Gunn is my husband's clan. Plus it put the people in my life who have told me they wouldn't call him by Aengus in their place, since no one wants to call a child Gunn, no matter the family connection.:) So I say go for it if you like Angus Stanley. Remember that you're the one who has to yell it out the door at dinnertime and if you love it, you won't care about the 's' sounds blending. Plus, if it makes you feel better, my oldest daughter is named Maeve Fenna and people who only hear it and don't see it end up thinking her first name is Mae as the 've' in Maeve blends with the 'F' in Fenna.
The name nerd in me loves Angus for it's clunky, Irish-pub charm.
However, in RL I'd find it difficult. I really like Stanley especially as a mn.
I think Hugh Stanley or Ewan Stanley are much more wearable. (Ewan is probably the front runner at least in the states but Hugh is doable with Hugh Grant still traipsing around).
I think it's kinda cute. :)