Nano reef upgrade help

Hi all,

I've had a rather interesting run of tanks lately and would love some input. Here's the short and sweet: 

I had RSM 250 which a enjoyed for a few years. We moved from Utah to TX and I decided to break it down and move it with us, and bought a Fluval Edge 12 to transport a few of my favorite corals, two ocellaris clowns, etc and to give them a home until I could get the RSM 250 set back up. 

I did get the RSM set up, but kept the Fluval up and running with live rock and a couple small softies with a simple HOB and heater. Worked pretty well despite the basic filtration, and we loved having the countertop tank - the design is beautiful. 

We decided to move back to Utah, and I decided I DEFINITELY didn't want to move the big tank again, so I sold it and moved my favorite critters back to the Fluval and I bought the Marine Pac 3 conversion kit to make it a proper nano reef system. This company seems to be out of business, and while the quality of the components seems good, I've had it running for about 8 months and it's been super finicky and flood prone if the siphon system loses suction (it's one tube in, one out from tank to sump). I can't leave the system alone for more than 2 days without a topoff and there's zero room for an ATO. 

Sooo bottom line it's time for a more stable AIO system. Thinking the Red Sea Max Nano, but it's spendy. Also curious about the IM systems. Any other frontrunners I should consider? I don't like the look of the JBJ or Coralife with all the black plastic. Fluval Evo could be in the running as well. Ultimately I'd like something dialed in that can be stable enough and easy enough to set up an ATO with - that can live cleanly on our kitchen counter. 

Pic of the current setup as reference: 

(sorry I don't know why it rotated the pic 90 degrees)

i really love my Innovative Marine 25 lagoon. I don't know if you're into shallow tanks, but its a great build, and is a large footprint. The tank is shallow enough that you don't have to go swimming every time a coral gets knocked over. I would absolutely recommend it. The hardest part is finding a stand. I had to have one custom made for me (by a WMAS member). There are commercial options available, the new APS stands are available, but i don't think they're necessarily attractive.

i did upgrade the pump from the stock to a sicce 1.5, as i've heard the stock pump is noisy. thats the only thing i've upgraded on the tank. i run an AI Prime HD for light, no skimmer, i did get some 3D printed floss holders and got rid of the filter socks. Im also running marine pure blocks in the rear chambers as well.