The 414's preamps are fine, based on you're recording to double speed cassette and the EQ is totally different than the 388's, it's like apples/oranges comparing those two machines. The 414's EQ is definitely not as good as the 388. Those points are pretty obvious.
The 414's preamps have plenty of gain, sound clean, do the job well. For a smaller unit the 414 sounds pretty good. It has some nice features and fills a niche. It's mid priced, (very affordable used), and mid featured.
It has the 4 LED level meters for each Input/Track & doesn't have a dedicated Master (L/R Stereo) level meter, but if you switch Inputs 1 & 2 to L/R, respectively, you can monitor the master bus that way while mixing down. Not sure if I'd call that a "hidden" feature or workaround.
It would work. It would be an adequate solution in a pinch. I'd much rather front end or submix using a 246, if that's your goal. A 246 or 244 would be a much better front end or submixer, as well as probably making slightly better sounding 4 track cassette tapes, basing that opinion on having much better EQ to work with (than on a 414). I also think the 244 or 246 has higher quality, better sounding components, heads and r/p electronics, but perhaps is another post altogether.