There's a chance you won't make much money after Ethereum mining is over even with other coins. Take a look at profits here:
http://whattomine.com/
You'll see profits are actually clumped up together between various coins. When Ethereum mining stops(due to difficulty or even PoS) people will move the rigs to other coins. Either they will just point it to another coin or sell the cards and buy cards that do better in other algorithms like the GTX 1070 cards.
That's the popular theory anyway, and probably true for the most part. However, I think it's important to reflect over the past year what's happened. Many miners this year got extremely spoiled when Ether jumped up in value and FOMO'd the hardware leading to the insane difficulty we have today. Last year we were happy to be making profits over a 6 - 9 month time frame as the price of Ether was sub $20 for a very long time.
The point is, if/when Ether becomes unprofitable soon, some miners will switch to other currencies or even get out entirely selling gear at reduced rates. However, there are several coins that aren't worth much today (LBRY, MUSICOIN, UBIQ, Sia, etc.) that you can still break even or turn a small profit mining them. If these coins see any sort of traction you could see some pretty large returns after mining a good amount of them. I think the key here is not to sell them if you think they'll go up (like many of us did with Ether when it was cheap) eventually. This is mainly why I'm no rush to get rid of my mining gear.
So yeah, I think mining is far from dead even if Ether mining may be (temporarily) unprofitable until the bomb is diffused.
Sure it's a gamble and small risk (what isn't these days) to keep your mining gear for these less profitable coins, especially if you haven't hit your ROI, but no one can predict the future. My strategy during the run up to the first Ethereum hard fork/bomb diffusion is to switch to mining a few different currencies (likely not the most "profitable" ones on whattomine, of which people usually just mine to swap for BTC/Ether) but ones with the most potential, in the long run, to go up and value and just hodl them.
I would be interested in what others' are planning on doing.