It's all a matter of taste. I wasn't a huge fan of the Lost Tales, either, actually.
But maybe a reboot gives a better chance at hitting a more relevant tone, these days. And a new cast (with let's say "classic appearances") wouldn't hurt the energy level, either.
But, if Valen's final fate was brought in only to give Sinclair an excellent write-off in the original series, will it be kept in a reboot? To me, it wouldn't be Babylon 5 without it.
Both Star Trek and Doctor Who have enjoyed excellent successes after their reboots. I do hope B5 fares as well.
