I take risk-reward ratio into account when I trade, but I don't base my trades entirely off of it either.
Like you said "do you think I'm losing too many opportunities that way?" Technically, of course you are, yet this depends on your trading style(s).
I also take trade/lot size into account, how long I plan to hold the position, and the type of profits I plan on going for, and my certainty of the trade I plan on conducting.
For shorter term trades (within the same day trades) I look less at the risk reward ratio because the market doesn't care what your risk-reward ratio is, place your stop loss and limit orders in places you decide based off your technical analysis. Then based off your technical analysis as well, you should be opening a position at the best possible place as well, which results in the best possible risk reward ratio with the smartest placements possible as well. When I trade for the short term I take smaller lot sizes because I can do these types of trades more frequently, I take very tight risk (so a close stop loss to my entry point, that is ideal due to my technical analysis), and depending on other technical analysis research I place limit orders to get rid of partial or my whole position. I highly recommend scaling out of a trade, meaning, get rid of part of your position and let the rest ride. This will allow you to put your stop at a better price so now due to some profit taking you just made yourself break even on the trade.
All in all, the shorter amount of time I plan on holding a trade, the smaller the lot size. Risk reward ratio is not thought about, but rather made based of technical analysis. Lot size may decrease as well if my certainty is not as ideal as I'd like it to be.
For longer term trades, I sometimes scale in and take larger stop loss areas. If I plan on holding a trade for a few days or longer, I often scale in so I can continuously take the best entry points starting with the tightest risk-reward ratio if it ends up going wrong. Then when I am in some profits I add to the position at good times and slowly trail my stop higher. Then after a little bit of that I scale out of my position to guarantee some gain in case the trade suddenly ends up going wrong. The only time I take longer term trades is when I am very certain on the position, therefore leading me to have a larger lot size, and potentially a larger stop loss size.
Take risk-reward ratio into account but don't base your trades off of it alone. My short term trades often have like a 10:1 or better risk reward ratio because I just open the position at the best price possible to where the price shouldn't end up hitting my stop loss. I would be dumb to just risk, a specific ratio for every single trade, not matter what the lot size was, how long I plan to hold the trade, my certainty of the trade, and the type of strategy I use on the specific trade.
Of course you should only take positions where you are very certain you will be correct, but sometimes for my shorter term trades, mostly scalps, I will sometimes make a trade even though I am somewhat certain about it because during those trades my risk reward ratio is crazy good like 10:1 or 20:1 etc.
Plus for short term trades, like scalps, there are hundreds, if not thousands of areas you can enter a position with like a 10:1 ratio or higher. Yet, that's only because I like to scalp, I tend not to hold most of my trades for more than one hour.