I'd say this is too rushed - but then this is very much opinion based (and I suspect this question will soon be closed as such).
As an example, Glasgow to Inverness is about 3.5-4 hour drive - I've done this a coupe of times. The road is not always the best. The travel back is another 3.5-4 hours. You are planning this as a day trip, of which you'll spend 7 to 8 hours just driving there and back. If you leave around 7 am from Glasgow, you'll arrive to Inverness around 11 am. You can spend half a day in Inverness - and will come back to Glasgow close to midnight. Inverness is a beautiful (if not very large) city and in my opinion deserves more than half a day after several hours in a car.
To appreciate Edinburgh, I wouldn't recommend any less than 3-4 days on its own. Again, in my opinion, it's not worth it. While the distance is much less than to Inverness (only just over an hour drive), you'll likely feel disappointed as you wouldn't have enough time to see everything there's to see.
Glasgow itself deserves more than a morning. There are plenty of things to see and you wouldn't want to feel pressured to quickly move from one place to another.
On the whole, as a matter of my personal opinion, I would recommend that you skip Edinburgh and Inverness on this trip. Use one day to do a road trip into the lower highlands, toward Ford William - it's a beautiful drive through the National Parks, past the lochs, with great nature viewing spots (of course, if you're into this sort of things). Then use the remaining one and a half day to see Glasgow.
In your case, I would probably stay in Glasgow on Thursday, drive up north on Friday, then Glasgow again on Saturday.
Again, this all is just my personal opinion, having visited all the places you've listed and having driven the routes you mentioned.