I think what might help you is to come at this from a slightly different angle.
Start by identifying the restrictions and limitations imposed on your speaker system by your room. Figure out the type of speaker that will work best within those restrictions. Then try to find the best available speakers of that type that fit within your budget. Work "big to small" as it were. If you start with price as your first consideration, you can easily drive yourself nuts because there are so many choices!
The room itself is a full 50% of any sound system. You cannot overestimate how much the room itself dictates the rest of your system! Your room tells you where your seat needs to go. That gives you your seating distance, which determines your ideal screen size and how much output you need from your speakers. The dimensions of your room tell you how much output capability your subwoofer needs, and whether you'd be better served with speakers that have very wide dispersion, or speakers that have more controlled or narrow dispersion.
You will also have other furniture besides your seat to consider. Will your speakers be positioned out into the room, with a good 2-3 feet of air all around them for towers or speakers on stands. Will they be going on a TV stand. Or maybe they're going in an entertainment or shelf unit. Or maybe mounted on the wall!
Lots to consider. And it all comes before price. Like I say, figure out the type of speaker that you need first. Then worry about price
So you've indicated that you have a very small room. What are the dimensions though? 11' x 14' x 8' ? 12' x 13' x 8' ?
Where will your seat be positioned? Where will the screen be positioned in relation to the seat? Where are you positioning the speakers?
Once we know all that, we can really narrow down your choices for you and make this much easier
I will say though, I very much like your choice of the HSU STF-2 subwoofer. It is more than capable for your room size. You'll never see me try to steer someone away from that excellent sub.
For the speakers, right away, I can suggest what are easily my favourite speakers for small rooms and just about any placement situation. Those would be the extremely versatile and extremely good
Ascend Acoustics HTM-200SE . I can promise you, they ARE worth the money. The SE tweeter alone is worth the money. It is a WAY better tweeter than anything else you'll find at this price point. And that means superb detail, superb clarity, and superb realism without ever sounding harsh, "bright" or fatiguing. It's just a really obvious cut above when you compare it to anything else in the price range, or under, or even slightly over, for that matter!
More than that though, the HTM-200SE are better able to handle just about any placement than virtually any other speaker. They are sealed and have controlled dispersion due to how the drivers are arranged. So you can place them close to a side wall. You can place them close to the wall behind them. At just a bit over 6" from front to back, you can mount them on the wall if you like. You can put them in an entertainment or shelf unit. You can put them on speaker stands, or on a TV stand. It doesn't harm the sound from the HTM-200SE the way it does with most other speakers. The Pioneer speakers, for example. I love the heck out of the 2nd gen models, but they are larger, rear ported speakers that really need to have 2-3 feet of air all around them in order for them to sound the way they're supposed to. In a small room like yours, you're very likely to have some placement compromises. The HTM-200SE will simply handle those compromises better than pretty much any other speakers.
They're easy to drive with pretty much any AV Receiver. And they play low enough on their own to really blend perfectly with a good sub like the HSU STF-2. They're just a great match for just about anything you might want to do!
So a pair of HTM-200SE for the Front Left & Right, plus the HTM-200SE C centre will set you back $464 with shipping included. That leaves you $136 to get a pair of speakers for your surrounds, which is fine. The surround speakers do not need to be identical to your fronts. Their job is to create ambience, envelop the listeners, and play the occasional sound effect. So some small, inexpensive surrounds will be perfectly fine.
I like the little
Emotiva XRM-4.1 pair as a pretty good sonic and appearance match for the three Ascend HTM-200SE across the front. At $179 shipped, the XRM-4.1 put us a wee bit over budget. But if the Ascend speakers didn't have their $38 shipping charge, it'd be just about perfect
I'll say this though, the Ascend HTM-200SE Left, Centre & Right with the Emotiva XRM-4.1 surrounds and HSU STF-2 subwoofer is a HECK of a good compact speaker system! Like, really really good! That will put anyone theatre you've ever been to to shame! The clarity and accuracy will be really obvious. And you won't wonder for a second where the money went or why these speakers are worth it vs less expensive speakers. You'll hear it right away and you'll know it was money VERY well spent.
I'd be excited about that system. It's more than worth every penny.
I will also say, call all three of these companies: Ascend, Emotiva and HSU. You will find that all three of them have excellent customer service that will make you feel that much better about buying from them. More than that though, ask about any possible deals and ask about any possible "B-Stock" on these particular models. You might be able to save some money and make this package even more affordable. So it's definitely worth a few phone calls
Best of luck! And I hope this will be helpful to you