We've been spoilt over the years with players who could score high teens/20 goals pretty much every season: Trundle, Scotland, Sinclair, Michu, Bony, Ayew, Llorente, McBurnie, Piroe.
I think it's pretty clear that while Cullen, Vipotnik and Yates all have their respective strengths, none of them is likely to be regularly scoring 15+ goals per season. We also can't play all of them in the same 11, unless some of them are way out of position.
Best case scenario (without a huge influx of capital) is what others have said earlier in the thread, we get better at supplying whoever we have up-front with chances to score. It's not as if our front players are missing lots of good chances. Eom in the second half is the only player I can think of from yesterday who didn't score when he should have. If one of Vipotnik's efforts from outside the area had gone in, or the instinctive effort that hit the post, that would have been a bonus and a Piroe-like goal. As in, more down to the striker's ability to make a chance for himself.
Perhaps Widell will be a difference-maker, perhaps Eom will blossom playing as a 10, perhaps we'll miraculously find a cheap and gifted creative player this summer, perhaps our wingers will suddenly get better at providing the striker with good chances, maybe we even stumble into a manager who can get us playing in a way that creates more chances, who knows?