Dream Girlfriend is more of an expensive game than Moe Can Change overall, I think.
While DG is actually very generous with free gacha tickets (you get two every week if you log on every day), the gacha system isn't separated into "themes" like MCC. It draws from a large pool of outfits so you'll be getting a lot of repeats.
Also yeah, like the above person said, you'll barely rank high in events unless you have energy recovery items... or the special event link outfit. In MCC (without tie-up outfits) I can still rank high enough to get the unique event ranking accessory (top 1000) without using energy drinks if I'm diligent, but DG really favors people who sink money into the game.
All of the special gachas (that pop up every now and again) require real money and it's absurdly expensive for what you get in return. You're not guaranteed an outfit, so sometimes you'll essentially get just a head accessory for around 2 USD. Ouch.
I guess what DG does better than MCC is that it has more detailed artwork; it has three different skintones for you to choose from AND three different heights; and it allows you to be a bit more interactive with your girls. Each event now has event scenarios, so you can see little stories featuring your girl (the stories will differ pretty widely depending on her personality type). And, oh yeah, they've added voices a few months back too (the voices also vary depending on personality type).
It's actually a decently fun dress up game but it might not be as fun as MCC if you're a purely free player. Also, it does take a lot of space on your phone so you'll have to be wary of that as well. I liked it enough to stick with it.