The only real answer to this question is that right now you can mine the most crypto from any given hardware in recent litecoin history. It is without the doubt the best moment to be mining, and people in a few years would kill to be able to mine .2 litecoin a month, just like people wish they could mine anything close to .2 bitcoin a month today on a small peice of hardware running on your desk 
This is where I find the disconnect between BTC and LTC. BTC is actively being developed, but LTC feels abandoned by Charlie Lee and no one has really stepped up. I still like that pooler put in a lot of work with litecoinpool, cpuminer, electrum-ltc. And you jstefanop with this ASIC miner, bfgminer, etc. Hard to say if LTC community can really step up with the coding side of it. I haven't seen any commits in over a year.
For the question on why I personally am working on BTC over LTC (even though BTC is in my pipeline
) is simply because thats how I got into crypto back in 2011-12, whats also more exciting for me is the fact that LTC is an order of magnitude smaller than BTC in terms of network hash power, community etc and thats a plus since the stuff im working on I dont need to sell 100's of thousands of units to have a material impact on the network. As for the dev side of things, there is a lot of stuff happening in the background that you cant see simply from commits etc. Version 18 of the node is about to be released, and we are pretty close to testing the wimblenimble extension blocks on the network, which will be a huge update and set LTC apart even further from BTC.