I'm intending 0.8.7 to be the last stop-gap before the finished version (not necessary the final release; just one with all the basic content to go from start to a definitive finish, some extra sidequests and more bugfixes will inevitably have to come after that), so now's the optimal time for testing so the main release can get off on good footing. Things might fall apart in certain areas, namely the desert, but there's still solidly around 20 or so hours you can get out of it now. Finding and fixing actual bugs would be nice, but I'd even be happy to hear thoughts about DR's untraditional battle system. I've never heard feedback about it, well, literally ever. Balancing, too, especially as you and foes use the exact same spells and skills; something that's overpowered against you is overpowered FOR you, too.
As for moving towards that finished version, my rough goalposts are something like, say, two months to finish the last remaining desert scenario (which is probably the single most complicated and granular part of the whole game), a month on each of the four core endgame scenarios, a month for bridging segments between the maingame and endgames (basically, your conversations with Damian after artifacts 7/8/9), and then maybe a month or two on some sidequests and some extra sprites (extra here meaning actual dead sprites, and not just Xes over people's eyes). So that is, say, September? I've never hit my goals before (usually because of a lack of motivation or pressure to stick to a date), so we'll see how that actually pans out.