SLPP will win the election that we have to admit
In my opinion too much power for anything is bad (SLPP or UNP)
Specially things like 2/3.
I always believe opposition should be strong to challenge government. So government would know if they mess up they will be replaced anytime by people.
This did not happen back in 2011, 2012. This is the reason MR did so many things which left him 2015 defeat. If UNP was a stronger opposition MR will play carefully and more responsibly.
Then 2015 Aug UNP was a weak government. They did not get a majority but unfortunately UPFA ministers supported them for so many things which require 2/3. They even got 19A by 215/220 votes
Final moments SLPP got stronger and MR was back, then even UNP government keep messing up and finally Gota won

Now we have restored previous government which was back in 2011 and 2012.
You see people are helpless they have no option unless change same people time to time.
My only choice is when it comes to general election choose the party based on the people we elect. Try to elect best politicians from your district, then decide the party

If you really want to go for a party atleast promote good people.
For SLPP try to bring these viyathmaga people and see what would happen. If you vote for UNP try to bring people like new better people same with JVP (No need to worry about individuals as they will get maximum 1 seat from a district).
We need to slowly change the heads in the parliament (government and opposition too) and always promote good people from any party without being slaves for a party. This is not a game that your party won and you celebrate. The actual results will not come on election day but end of 5 years