1994 Ford Bronco still loss of power

My bronco only got about 60% of the power it had when I first got it a year and 8 months ago when it had 85000 miles on it. Within the last 6 months I changed the air filter, fuel filter, plugs, wires, distributor, o2 sensor on the exhaust, and a throttle bore service. Also when I first got the truck I use to get on average 13.5 mpg and now I get 10.1 mpg and still decreasing. Also the truck really lags at half throttle and it will go better at quarter throttle. I was told to put some fuel injector cleaner in and engine restore, but I was also told to watch what I use cause it might cause more problems then what I got. So I am asking for any suggestions at all to regain my power and fuel economy, or what kind of injector cleaner I could use and if engine restore is ok to use?
thanks to all,
Leon