There are some Japanese plug and play ECU's but I don't think they're programmable by the end user, and I doubt they'd have an English software interface anyway, even if they were
The other choice is piggybacks. E-Manage Ultimate, which can be programmed by the user but requires you to hack the loom, and HKS F-ConS, which has adapter looms but requires some special software that very few people have access to. Either of these would be ok for street use on a midly modified engine. In fact if I could program the HKS myself it'd still be on my car.
After that point you get into the terrority of standalone ECU's and making your own plug and play adapter. Not too much of a problem with a manual ECU, as you can just biff the stock ECU and plug an aftermarket one in it's place.
However the Tiptronic ECU also serves as a transmission computer, so you either have to replace those functions with another computer (about $1200 for a
dedicated Transmission unit), or continue to run the stock ECU in piggyback fashion, which is where it get's ugly. Not all aftermarket ECU's will happily share inputs and you need to duplicate some sensors as well like the temp ones. Even then I don't know if it will work without throwing a check light and going into limp mode because the engine isn't getting the correctly timed return signals from the ignitors or some other seemingly insignificant problem which cases it to fail. Then there is the issue of the interface to the ABS/VSC/TRC computer