@consolatio You are mixing two different asset classes just because they give you tax benefits. Keep aside the 80C benefit for a while and think of your investments outside of that context, your eventual aim is to have an asset allocation (debt and equity) that you are comfortable with, and a decent inflation beating return.
Out of this, when you look at your debt allocation, PPF is one of the best instruments to get best possible returns in the debt category. When you compare PPF vs FDs, also, PPF is better from a returns perspective, not so much from the lock in perspective. If a person in your position is OK with the PPF lock in period, one could reduce one's future FD investment and divert those funds to PPF OR one could break the FDs and move the funds to PPF (or move them on maturity).
Coming to ELSS - I started with ELSS early on but stopped investing because I am not comfortable with the lock in for ELSS. Also, there is no other instrument equivalent to the risk and returns profile of PPF, but for ELSS, you can find non-ELSS large cap funds that have similar portfolio (and no lock in) so I went with an Index fund that will give me returns in the similar range without the lock in associated with ELSS. I personally am OK with the PPF lock in because PPF is close to sovereign guarantee, I am not OK with ELSS lock in because ELSS is market linked.
The whole point is look outside the 80C, your investment is for the next 10-20-30 years and tax saving is a very small part of that. Do not let tax breaks/rebates decide your investment allocation. One should decide their own allocation and then try to accommodate for tax rebates.
When the new tax regime kicks in - you are not going to get 80C benefit in the future anyway.
Note: I am just making a point, this is how I have structured my financial decisions. This is not financial advice.