The Sony 45es is the most recommended if your still in the 1080p camp would be a generally significant upgrade or a used 1080p JVC would be a drastic improvement over your BenQ. If 4K is your thing the Vivitek 2288/Optoma uhd60/65 would be a good improvement although contrast would be no better and game lag may be a problem. Their are the new 4 way pixel shifting DLP's also but contrast is likely to take a hit. The Epson 5040 or JVC 420/440 could be winners if your closer to the $3k range. The 5040 biggest flaw is its 10gb HDMI and JVC's are ridiculous lamp cost.
"Smart enough to know better, to old to care" ------ Dedicated Bat Cave Home Theater, JVC RS49U/Mitsubishi HC7900DW Projector, 110" 16:9 Jamestown screen with variable power masking for CIW 2.50:1 to 16:9, Marantz 7009 with 7.1.4 Atmos with Ohm mains,3 DIY Subs (2 15" (1 ported, 1 sealed and a 12" 4th order bandpass), 1 DIY butt kicker, Custom Built HTPC, 18TB DroboFS NAS