I think it depends on what you mean by slightly included. Just like diamonds there are different levels of inclusions. I have two sapphires, one pink and one blue and they are not included at all. You really need to see them in person to tell if you are comfortable with the inclusions. I've seen lots of rubies that have visible inclusions, but not so many sapphires. It all comes down to what you want to pay and what you are comfortable with. HTH.
As far as inclusions go we often describe anything that you can see under magnification as an inclusion this may be the slightest bubble or mark but to the naked eye looks great. So if it looks okay go for it. Remember you are dealing with a natural product and mostly no two are the same .Id rather a natural sapphire or Ruby with a slight mark then a perfect lab made one anyday!
(Beware most lab created stone has added inclusions to make look like the real thing)