Eureka used to make the same basic tent with a full front vestibule. They were reviewed favorably in Backpacker, except for the zip on the vestibule, that leaked because of no cover flap. Why in the world did they leave out the zipper flap? No idea.
You sound about to get hooked on the MYOG cheap tent modification syndrome, for want of a better description. I am a recovering cheap tent modification junky. I spent years tinkering with another old Eureka solo model, trying to get the weight down. Carbon poles, lighter fabric floor, removed door and replaced with 'beaks' on the fly to create a vestibule. Then the poor quality fabric on the fly started leaking in heavy rains. So after all that work, I had to replace the tent.
That's why I agree with Ben. Get something of better quality in the first place.
The Eureka is a 4 lb. solo tent. Yes, the 3' by 8' space with a dome ceiling is nice. But there are other self-supporting tents out now in the 3 pound range, made of better quality materials, and there are more coming out every year. They used to be narrow 26" wide coffins, but the REI TT is now 39" tapering to 24" (Why the teeny door - no idea). And there are other new ones coming out. Luxe has one that also tapers, as does the EMS Velocity 1.
The only way I would do it again would be if replacing the fly with a high quality silnylon one were the first order of business. Lighter, and you could add the beaks (vestibule)in as part of the new fly. Maybe you could find one of the older Eurekas with the full fly, and either use it, or cut it up to make pattern pieces for a sil fly. Then the tent would be lighter and storm worthy for starters, and you could take your time finding the right carbon poles and lighter floor material, such as black tinted 1.26 oz. cuben sold by Zpacks, or the dark gray Shield silnylon sold by Thru-Hiker.
That's would be the only way I would ever get sucked back in to MYOGCTMS again.