My question is, should I reseed this Fall with straight Midnight again in an attempt to get the lawn to look more consistent?

You can, but you may spend the next decade fighting with the old grasses that you don't want.

If you have very small patches of them, I'd use Roundup on them to kill just those spots off. Then, once you're sure it's dead, reseed.

If it's stitched in throughout the lawn, I'd be very tempted (more than tempted--this is exactly what I did!) to Roundup the entire lawn and start over. Since it sounds like this is what you have (you mentioned competition), this would be the better idea.

Yeah, it hurts, causes emotional distress, and otherwise ticks off the neighbors. See the thread "Execution at Dawn" for my photos of the progressing death. The new lawn will be much nicer, consistent in growth rate, and easier to keep.

You have a new house. You and not satisfied with the original lawn or the overseeded lawn. For the highest quality lawn, do as Morpheus suggested. That would require a complete kill and re-seed. Be sure you can properly water any area that you intend to renovate. Use only highest quality blend of seed.

Use only highest quality blend of seed.

Excellent point! Anything you find on the shelves at the big box stores is not highest quality seed...

I guess it depends on what your goals are. If you just want a thick, green lawn for kids and pets to play in, go ahead and overseed. If you are looking for a perfectly uniform capret of grass, you may as well bite the bullet and start over. While overseeding with give you more midnight, it isn't going to get rid of the other grasses. You will always have different shades mixed together.

Frankly, 95%+ of people could care less if they have slight variations in color. Posters here are in the extreme minority when it comes to lawn standards.

This is a nicely landscaped lot on over an acre, so killing it all would be really out of the question.
My question was not should i start over, but really whether I should stick with straight Midnight or get a KBG blend?
Hypothetically, (I know that is not possible on this lot)what if anything would be wrong with a 100% Midnight lawn?

Hypothetically, (I know that is not possible on this lot)what if anything would be wrong with a 100% Midnight lawn?
I'm sorry, I don't understand, particularly the part in parenthesis.

Kachinee, be patient with us, please. The guys were trying to offer the best advice because your question was a little ambiguous and didn't give us much information. Ambiguous because you complained the grass looks inconsistent, and you want to add another texture. Not much information because we didn't know the limitation of there being such a large area. The guys answered the best they could with the best advice you can receive based on the question and complaint. Please understand, they're not going to tell you "Yeah, do whatever." You wouldn't seek that kind of advice when you can make the decision on your own.

Now we understand starting over isn't possible, but allow me to point out a blend will be adding still more textures at possibly different rates of growth. As long as there are so many different varieties in the lawn, it will never be consistent. You can do it for years and it might get better depending but not complete.

Midnight is susceptible to powdery mildew, but that's generally under conditions that favor the disease. Is the land shaded by trees or anything? We could probably tell you about Midnight and your rust problem, but we need to know what state you live in. While Midnight is often fine as a monostand, you'd ordinarily sow it as a component in a blend, but your problem can very easily multiply and defeat the purpose for the effort (which is to achieve consistency) depending on the other components in the blend.

Is it possible you can divide the acre into more manageable sections to begin the project to start over since that's the best thing to do? I also wonder how you'll irrigate an acre. Do you have a sprinkler system? Forgive me, I know you didn't ask about that either, but it's necessary to keep the seeds moist or you'll waist an awful lot, most of them in fact.

"Ambiguous because you complained the grass looks inconsistent, and you want to add another texture."
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I am zone 5 and I have an irrigation system which I used to grow the lawn from seed in the first place. I have KBG in the current lawn, so I did not think I was adding another texture to the blend of grass I currently have by adding the Midnight variety. As an anaolgy, I like straight Romaine salad, but mixed greens are OK too, just so long as it is not mostly plain iceburg.
This 1.25 area is exposed to full sun with no mature trees.
Eventually, a small section between the sidewalk and street (less than 10%) will be shaded by street trees. I have a problem on the curb with snow mold or die-off because of salinity from street salt, so I was going to seed that with Moonlight this Fall. I was planning on overseeding the rest with Midnight from Lesco.
The reason I wanted to add Midnight in the first place was to get some darker color in the blend. I overseeded with 50 lbs. of Midnight last year after aerating.
Having it all consistent is not enough for me to kill an acre of lawn and start over. I want to improve the color and
possibly get more KBG in there.
The rust problem last year was pretty bad.
I am really concerned about that coming back again in late summer/early fall. Last year when I cut the lawn it got all over my shoes, clothing, coated the lawn tractor, and just got everywhere.

If it is any help, midnight ranks near the top in rust tolerance in most states' testing.

If you are concerned about the rust returning this year, you could apply some cornmeal now. It is a mild fertilizer and seems to ward off many fungal problems. Both of those should help with a rust problem.

Bill, that's what I was thinking, but it seems to vary depending. In the east, Midnight is terrible for rust resistance. Head west and it improves signifcantly. Seems to be common with most of the Midnight types. That's the reason I asked where she lives. Results are taken from NTEP trials, but if you have specific ratings I'd really appreciate it. I expect a lot of people would. I'd love to be able to narrow it down.

I'll defer to you about specific KBG's, but it is rated fairly highly for rust resistance overall. The year-to-year and site-to-site rating for disease don't seem to be very consistent. Disease might be a little too hit or miss to draw conclusions from just 1 or 2 test patches.

Anyway, rust is a disease that is controllable through cultural practices. As long as a grass isn't particularly prone to it, rust resistance would be low on my priorities when picking a cultivar.