What do you mean by feature exactly? Something new added to bitcoin?  The only thing that makes the value go up is more demand so we need more people on board for that to happen. Keep spreading the word if that's what you want to see.

Even though bitcoin is very well equipped, I think about one feature that will make bitcoin more valuable and more useful, and that is the "smart contract" feature similar to ETH. Today ETH is used widely just because of this feature. A lot of start up companies use ETH to make their own tokens based on that smart contract algorithm which makes ETH is one of the most used and appreciated cryptos of all time, second to bitcoin.

I think, if smart contract can be made available for bitcoin, it will not only increase the utility of bitcoin, but at the same time, make it more useful for the companies around the world who wants to make their own crypto footprint. More utility means more demand and for the same reason, the price can take few more steps towards moon. Just my 2 satoshis!

The main feature what I would want is the smart contract feature like eth which would make it widely used as an utility coin as well just like eth being used today. So even the more demand will bring more and more people in the queue to have more and more btc so that the present downfall stops.

Couldn't agree more! Otherwise btc will be pretty much useless. There are no use cases for bitcoin at the moment.

This is two different questions, what can make bitcoin more valuable which is topic question? Beign conservative, not innovate too much, leave it to all altcoins and look them burn. Take out best from ashes and progress slowly but surely. This will increase price always.
Price go up from various reasons, most from will to get rich quick.

No new features need to be added bitcoi  is already a popular currency and the demand is increasing day by day, so nothing else to do.

the price will go up when it's good and ready. patience is a virtue.

non-linear scaling mechanisms like the lightning network (once user-friendly) could make BTC more usable and therefore could encourage increased network growth.

but ultimately, there is no "feature" that is going to change things drastically. bitcoin's primary use case is money. it has a limited supply, so as the network grows, price should rise. enjoy the ride!

No, when a Bitcoin transaction is unconfirmed for a very long time there's a possibility that it gets rejected and the spent Bitcoins will be sent back to the address. Nice suggestion however you didn't fully answer the question of OP.

I can't imagine any new feature that could make Bitcoin more valuable because every feature has pros and cons. Smart contracts would be cool to see but I doubt that it could boost the price of Bitcoin and it's not new if you're familiar with ETH.

We need the lightning network, bitcoin is a currency and the lightning network will make bitcoin overcome its biggest problem which is the scaling problem, once that is taken care of it could be a good idea to have some optional characteristic that made bitcoin truly anonymous for the users that want or need that, and finally smart contracts are a good idea as well.

This is an important question and only well knowledged members who have been trading in cryptocurrencies can answer it precisely.
Besides the anonymity and fastest network confirmation, bitcoin should be accepted globally including minor business owner, this is only possible if governments will allow bitcoin as a legal coin