I'm glad this was revisited but, sadly I don't really see a great way to handle this. The male channeler is a pathway to Dreadlord through the DF system (which needs revamping, from what I hear we're working on a new improved system), and or you can roleplay however you want from there as a murderer or good guy, whatever.
Sadly, once you begin to taint the charachter will progressively become unplayable and it's a waste of time if you don't pursue the alternate route through being a DF, as sad as that may be.
I do think Dragonsworn should have the no-taint flag added after r5, but only because their behaviors are policed by the clan i.e. they can't attack innocents, etc. I don't think it'd be great to have a bunch of essentially Male Aes Sedai running amok pking ds because quite frankly it's going to tip the scale some and make it fairly uneven. Additional HPS seems somewhat warrantable but, it's not a mean to an end. The player just has more hps now and becomes useless with more hps vs with normal fc hps.
I think if Dragonsworn was allowed to have no-taint at r5 for MC chars, that would be fair/difficult enough. Maybe restrict weaves on MC's to that of unranked FC's and only give MC's full weave or close to full weave (no sleep, port, incin) at r5+
At least they have a home if they so choose to go that route and char progression is available. I'm personally convinced that it won't contribute much though because the Dragonsworn as a clan have not really made an impact as a clan just yet. It's kind of useless.
I'd be interested to hear your thoughts but, they're right: the player base is smaller than it used to be. I think we can combat this influx of mc's with no taint fairly easily with making clan weaves available at r5/immunity to taint at r5 or at a certain alt qp for DF if they so choose the other route, but at least the character has options and can escape dooming their alt.
I'm sure this requires coding but, for what it's worth it would police this some and still provide an attainable although difficult path to still enjoying a potentially powerful character. They just have to work at it some more and in my opinion, they should - channelers are the ultimate weapons.