What is "mix workout"?
Anywho, I think your best bet is to formulate a gameplan and stick to it. If it was triceps day, work triceps. Don't give in to the urge to flip-flop back and forth between a bunch of different exercise philosophies. It will end up messing with your ability to accurately gauge the effectiveness of your current workout. Sounds like your doing a pretty basic bodybuilding split. I'd say do that and only that for about 3 months, then reassess your goals. Chances are if you stuck to it like glue and worked out consistently you'll be seeing pretty decent results by then and you won't want to change, but it will feel good anyway to have set a firm date and gameplan and to have completed it.