Please check your portfolio overlap. MFs are already diversified, and you are doing SIP, further reducing the risk. Your investment will be over-diversified.
Better if you make a portfolio of Index+Flexi+Small cap fund (select any one from each category) but as you have a long-term vision and if you take a little extra risk, choose flexi-cap, multi-cap, or small-cap funds and do SIP.
I prefer index funds over large-cap funds because ...
For sure, You should keep a track of the parameters. Especially on the criterion used while selecting the MFs. If anything is compromised, you should look to churn.
But don't just look for returns, dig deeper, the market doesn't move unidirectionally so there is a need of having...
It depend on market conditions, works only with higher volatility and trending market situations. Usually market's moves within 1% in a day thus, as per my understanding, Long Straddle is quite a risky strategy. So use it with caution.