Just remembered--I used to recommend the Bushnell TRS-25. I don't anymore, as the price has inexplicably dropped from ~$90 to $40-$50. That's not a great sign.
Instead, I think the Sig Romeo5 fills that niche these days. Small-ish 'dot (the number is frankly meaningless, as manufacturers straight-up lie, and most folks have some degree of astigmatism), holds zero, doesn't cost stupid money. About the only downside is that it uses push buttons for brightness control. A knob would be much better.
And yes, I know a lot of guys recommend the Primary Arms Whatever the Hell It Is, but I just can't take that company seriously. They scar every optic they make with their garbage logo, which is literally just their company name in a free-ware font.
I don't think they take themselves seriously, either.