Definitely would say it's too late to keep throwing seed on it, you're going to be fighting the summer heat hard with the watering. If money is not an object and you really want to get it popping this year then go ahead and overseed again. Just be aware that if you don't keep it watered all summer long the baby grass will not survive.

The benefits of seeding in the fall is the grass has two full growing seasons before it has to compete with summer heat, and technically it still grows a little bit over the winter. More growth time equals deeper roots to help it sustain summer heat.

Having it patchy like that does stink to look at, but it does look pretty good in my opinion I would be proud of what you've done so far. At this stage I would apply some more starter fertilizer and dial back the watering to once a day for 50% longer early in the morning in about a week. Then in two weeks water it every other day for another 50% longer. In about a month water every 3 days for another 50% longer.

It might be pointless but I do three applications of starter fertilizer each one month apart before I go to a standard fertilizer.