I like NEO and Stratis. But anyway my vote is for Stratis. I like their aspiration to development of technologies.
I definitely agree that those two has the potential specially Stratis. There's a lot of movement on the part of Stratis dev and I think if they have completed in time, they will surely gain a lot of looks from investors. But I'm not sure though if they are behind schedule. Last time I check they should have released a June update.
As for NEO, we all know that this is the Chinese Ethereum. Although the latest news from China really affected the price of NEO, but since rebounded to $50. I think the banning of ICO by the Chinese government really affected NEO. So it will take years before it became Ethereum Killer. But let us see how things developed.