Your offense looks fantastic for a 16 team league. That's usually the best way to go about things. Hitters are safer bets and are also typically valued more highly than equal level pitchers (for good reason). So IMO you certainly took the right approach in your draft.
Even so, I'd feel a lot better about your team if you had a true ace. Like you pointed out you have a lot of quality pitchers with a decent amount of upside, but you don't have a pitcher or two capable of carrying your team should some of your other pitchers go on a cold streak. I'm also against completely punting any one category. While you should win holds most weeks, holds in general are even more volatile than saves. So you could still lose the category occasionally if your opponent's RPs have more hold opportunities in a given week.
At this point an ace would probably be tough to get without sacrificing too much of your offense. I'd suggest waiting a couple of weeks for a reliable top starting pitcher to struggle (at least a few elite players will start out slow, just keep your eyes open) then go in for him at decreased value (just do your best to hold out until then). Also, while you don't need to make a trade for a closer, you really should have one or two on your team to give you some chance at the category. Keep your eyes open for a decent option on the WW (closers rotate fairly often, so this shouldn't be terribly difficult).
Just work on improving your pitching a bit. If you can do that through a good trade or some decent WW moves, you'll be in great shape.
"Don't take anything for granted, because tomorrow is not promised to any of us." ---Kirby Puckett