The fleet type that most urgently needs replacement - well the Charger sets are gonna replace what - the Corridor Rens, the LRCs that didn't get the refurb and some HEP2s? Cascading Canadian cars to Ocean - that's the sleeper Rens gone.
Those 10 trainsets are covering VIA's harshest and most remote routes with the exception of Jonquiere/Senneterre. Why should they not have reliable stock, and accessible low floor boarding rather than depending on traps, and a cabbage on the end for backup moves in Edmonton or when CN puts yet another freight on the ground. Not to mention the possibility of shortening the train lengths with the extra capacity and therefore being able to wye at TMC instead of the ridiculous move via the Newmarket and York subs to get out of Toronto.
Hell, if we are talking about minimising fleet types, why not cut bait on the token RDCs and base an F40+bilevel coaches+cabbage in Capreol to operate White River. Pretty sure there was some chat about going locohaul up there anyway a while back, and ensuing discussion about the wye at White River.