Riceberry made a calculation here.
https://bitcointalksearch.org/topic/m.16807597
It could be quite profitable to stake, but of course it depends on market. Crypto is quite hard to predict long term.
Let's consider three cases.
1) Stake at ICO marketcap (1 million USD)
2) Stake at STRAT marketcap (7 million USD)
3) Stake at Waves marketcap (30 million USD)
HEAT seams most similar to Waves, so it should reach it's market cap in the first couple of weeks/months.
HEAT unfortunately is a two man show, with limited resource.
Your other examples have teams of devs and operations guys. HEAT will not reach STRAT or WAVES levels until they expand the team. They can't physically deliver a complex crypto project on their own.
AFAIK Stratis is two man show too. Also, according to HEAT devs, they are in the process of recruiting more people. Also number of people does not exactly equal immediate success. Waves had more people than HEAT and could not deliver full nodes at launch, instantly making the price plummet after launch. HEAT decided to take the other route - delaying the launch but launching with full nodes. The market will probably prefer the latter one. Anyway, trying to figure out profits of staking HEAT.
Stratis is definitely not two man show. They have half a dozen people and growing.
Waves had too much resource and not enough direction. They also messed up on some delivery aspects - as you mentioned.
HEAT needs more headcount if it wants to sustain a good price. However $30M mc is not possible with just two people.
AFAIK Stratis started with Krushang and Chris, then they started hiring more, like Nicolas Dorier etc. Anyway, same thing here. Started with two guys, hired the guy to write the blog posts, in process on hiring more people according to what they stated. You will have your half a dozen people team soon. Anyway, what is important is the results of their work. Many people were disappoited by Waves launching without full nodes and postponing them for months. HEAT devs are smart avoiding that mistake. They had two options - launch half baked product like Waves did (and trade below ICO like Waves did) or wait like LISK, ETH, Augur etc. did and make the project more successful. Of course people can be angry beacuse it all takes much longer than expected, but so were LISK and ETH investors when they had to wait. Anyway, we will see soon what HEAT devs delivered, and if they really will launch with full nodes and with partnerships in place they will be greatly successful. Now it seems like the race between HEAT and Waves which coin will deliver some of the similar feature. Waves is winning at this moment, with 30 million market cap, but if HEAT creates superior product we will see huge gains here. Look at the picture that someone posted here. NEM was in similar situation and at some point hit even 100 million market cap, starting at one digit million market cap.
let talk again, when its end of February and waiting for full network or working features.