Have done lots of diy on my home but this one has left me with some questions that I'm hoping to get some help with...

I have a covered breezeway between my home and garage here in SF South Bay area, Northern California. We get rain and cold, but not too much humidity. Space has heat and A/C, but I'm not intending to rely on either. The floor is brick 1" tile, -looks like solid brick but isn't, over concrete slab, -about 4" thick. Surprisingly level and flat. Exterior walls have concrete foundation extending minimum of 2" above brick floor at doorways with framed and insulated and rocked walls with doors and double pane windows.

Intend to make this my office and considered Ditra isolation and tile, but prefer solid hardwood to match the rest of the house, (which is not contiguous). Prefer look and feel of hardwood as well.
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Had some experienced installers look and quote. One said: "Glue down plywood substrate, solid oak over and finish" Sounds reasonable, but I'm not sure the glue will provide an adequate moisture barrier.

Another said: "Impact hammer-nail down of plywood, (no mention of moisture barrier), and engineered product over ply" Not crazy about limited refinish option on engineered and impact-hammer seems like a weak attachment failure point waiting to happen.

So, kind of thinking diy again to achieve overkill subfloor at the very least. My handyman and I could install subfloor, and either install prefinished product or just turn over to installers to do traditional solid red oak, or prefinished Luazon no-bevel over it. Or we could just install the prefinished ourselves.

Area is about 14x18 or 252 square feet.

If I diy the subfloor, I would do 15 lb felt at 45 degrees with 3" overlap over the brick with a 12 mil poly layer over that and install 3/4" exterior ply 4'x4' panels with 1/2" exterior and 1/8" interior spacing for expansion. The ply would be masonry screwed down at 16" intervals throughout.

My questions are:

Should I just go with the glue down vendor-completed subfloor and traditional solid product and sanded finish? Moisture control okay with this option?

If I diy, would it be advisable to use exterior grade ply and is it valuable to seal your ply prior to install with a water sealant?

Should I just forget it and go tile....?

Thanks

Maybe consider an unfinished engineered wood. I know you mentioned liking solid, but you can get engineered that is 5/8" or even 3/4" thick. If you go with the unfinished version it has no micro bevels and would look just like solid hardwood when done. Plus these nice thick products will feel solid to walk on just like a solid wood floor. This would help avoid doing anything with the plywood.. Some good manufacturers of unfinished engineered are; Real Wood Floors, and Shamrock. Bets of luck to you.