I think streaks should have never been introduced to the game. I am sure they were introduced to encourage spending but feel expenditures were not increased. Expenditures to get into the top 100 are driven by rewards and not by streaks. I would have probably spent more without streaks. My reasons are:
1) bugs in the game which cause streaks to end antagonizes players. A streak ending because of bugs can result in the lose of 100s of gems to the player. This increases complaints to support who are not supportive. On the second complaint they tell you that you complained once before and get nothing. Even though the initial complaint received insufficient compensation.
2) the streaks encouraged cheating (although now hopefully fixed) which caused a lot of bitterness among players and guilds. Even though cheating was supposedly stopped, the benefits gained from cheating remains. The benefits of cheating would have been much more negligible without streaks.
3) OP heroes significantly annoy players. Especially players that invested money in heroes that were nerfed and are no longer very relevant to PvP. Make MK a challenge instead of an annoyance (after fixing the disease bug).
4) I would personally prefer to always fight the hard team. I find myself more frequently fighting the medium team to keep a streak alive. I prefer PvP that is challenging and fun and not just a grind to get more trophies from a streak.
5) there are a few weirdos that set their alarm to keep their streak alive from one day to the next. They need their uninterrupted sleep. Give those poor players a break. They may survive longer to keep spending.
6) streaks make me grumpy and less likely to be funny. I need to be funny if I ever hope to get a date with Victoria.