I would have thought doing the multi turbine time (Beech 1900 was on their website) would get you further up the ladder without you having to spend huge amounts of cash on jet time. It would still make you marketable and reduce the risk of you applying to an airline and having to either redo a type rating to their standard or worse still not be considered as they might form an opinion that your training wasn't up to scratch. It would also eliminate the risk of you ending up with say a 737 type rating when the market may be wanting airbus or ATR as an example.