If I was in the OP's shoes (and of course I once was) I would be looking for used gear that holds its value so that he/she has the ability to resell the gear if they want to try something different or when they are ready to upgrade their gear. For $1000 USD you can certainly put together a solid rig that may be all the gear you need to accomplish your goals.
While I do agree that doing some listening on archive.org can be helpful in making a selection. Yet I would take this information with a grain of salt as this method of research does not account for many of the variables that can make a recording sound great or sound terrible. Just as a for instance when listening to a random show on archive.org you don't know if the room always sounds terrible or if it has the potential to sound great under the correct circumstances. Or maybe the taper did not set up their mics in the best spot in the room and while the gear worked as designed the recording is less than optimal.
If I had $1k to build a rig I would keep the Zoom in the signal path for now and put that $$ to work on mics and powering those mics. Used DPA 406X's do pop up in the yard sale for $500 and then you would be looking at purchasing a batterbox or a preamp to power those mics. Right now there is a Shure FP-24 in the YS and I believe there is also a Naiant preamp available both are under $300. Paying attention in the Yard Sale to new For Sale offers will certainly land you a decent preamp or battery box. Church Audio and Naiant have sold a lot of gear to tapers over the years and their products do frequently pop up in the YS for a good low budget option. I think the DPA 406x's would be the highest quality microphones that fit your budget but you have to live with 100% omnidirectional recordings and that may not be what you want. Otherwise I'd look at putting together an Audio Technica 853 rig which is another good low budget mic and it gives you the option of purchasing capsules that use different mic patterns so you could figure out what mic pattern works best for your recordings. Paying attention to ebay is another good option for the gear I mentioned. I personally would rather buy used equipment off a taper than ebay but there are great deals to be had in ebay auctions yet you do have to take into consideration the risk associated with purchasing electronics.
Good luck!
This is all solid advice. Much as I love my DPAs, I would strongly recommend against buying them as your
only mics for the short term, unless you know really know how to use them and can ensure you will always be in a location where they perform their best.
I am a classical / acoustic recordist. Even though I am usually in auditoriums and churches with relatively quiet audiences, can usually place my stand up high right behind the conductor, etc., I definitely cannot use my 4061s for every concert. While the may not have the highest sensitivity, they are
ruthless with picking up any noise from the audience / house you
didn't want to capture (especially the HVAC hum you didn't notice during the concert). iZotope RX is almost always required when I run them, even if the hall seemed silent at the time.
You have to be careful about placement in very reverberant spaces, because they will grab
tons of the room sound. For acoustic recording, they usually need EQ correction if used with the stock short boost grids unless they are covered by clothing or beyond the critical distance from the sound source (85% direct-to-reflected sound ratio).
Then you have to get powering adapters for them or have Jon/Naiant build you a set of PFAs.
Bottom line: They are absolute magic when the right combination of factors come together, but there is definitely a learning curve with them and they are not the best in every situation.
Still waiting to hear about what OP is recording, but I think the AT853 will get you pretty far. There is also the Line Audio CM3 (now CM4) which I have found to be the most forgiving in terms of placement. Naiant makes solid mics also. The AKG option David mentions is very good. Avoid Church Audio.