What are your existing windows? If you have something like a steel or aluminum window (you mention aluminum...but that can mean many things to folks) the mere profile thickness of the new window will cause a reduction. An aluminum window is done as a full tear out normally and there isn't much to be gained. If your reference to "aluminum" is because of a storm window, while the glass size will be reduced in many cases on the primary window, the opening will feel larger due to the lack of a storm window.

no storm windows. frame is metal, dark bronze in color and hubs says they are aluminum. put in by builder when house built in 90's so super cheap im sure.

What's the issues with them? Operation, seal failure, other?

Seal failure - about half of them. Have considered the cleaning thing but it is so longstanding i fear it has etched the glass.
Should i look at just replacing the glass?

Love to get rid of muntions/mullions for more light but not loving the way these inserts give you less glass area. But i found something that said tearing out everything adds 10-20%. Tough for me on a tight budget. I think it was Sunrise that does it that way but dont know where they come in on quality or price. Any thoughts on that?

If everything else is in decent shape, they might be glass only candidate. Nothing is going to come close to the profile size of aluminum, but aluminum (Maybe steel too by that is much more expensive than aluminum). Do you know who made the aluminum windows? Found a label? Where is the home located (i.e. climate wise)?

Says Allenco on hardware, WOW.

We're just outside Memphis so pretty moderate climate-wise. It gets cold here but usually not bitterly cold for more than a day or two so not a huge deal there.

I'm curious why the choices now are mostly vinyl, fiberglass, or wood.

Was aluminum popular/cheap 25 years ago? Several houses in this subdivision have these but these are strictly "builder grade cheapest materials you can find" -type houses. i dont think anyone paid extra to upgrade to alumimim windows.

Allenco is likely just the hardware manufacturer and not the window unit. Are they single or double hung windows? Have you tilted one of them in or looked inside the head jamb for a manufacturer's label?

I wasnt able to find a label. They are single hung.

Can you look in on the side of the operable sash? They are probably side load windows in terms of removal.

im afraid that is a little beyond my paygrade WoW. I will keep looking for a label though.

Well, it turns out Allenco is the manufacturer of my windows. Local guy says they've been out of business for a good while but replacement parts are still available. So im moving forward with estimates on glass replacement and removing the grids.

If anyone has advice on that, I'd love to hear it.

Memphis stays pretty warm, but it is a split climate. Unless the window was a good aluminum window and performs well, the prevailing advice would be to avoid aluminum (i.e. condensation issues). There are plenty of slender vinyl windows that can work, but not many on the bronze interior side of things.