Based on the specs I would get S360DB.
For tweeter, S360DB is using planar which will have more "crispy" sound for 2khz and above, such as cymbals and guitar strings.
For bass, both same 4 inch driver but S360DB driver is 30W while R1855DB is 19W. More wattage can go more louder.
For subwoofer, both 8 inch, S360DB is 75W while T5 is 70W.

Interesting insider view on why current speakers sensitivity are rated as such.

Help to isolate the vibration to your table. It works if your table vibrating because of the speaker.
Can also use yoga block, does the same thing.

Use on living hall or desktop?

S3000 got bigger bass driver (6.5" vs 5.5"), have more lower rumble and bass impact than S2000.
But if use on living hall and need the low rumble from movie, better get speaker with sub-woofer.

If mostly for movie, especially action movie, get 5.1 or 7.1 speaker or whatever latest system now. Sub-woofer for the low rumble and center speaker for dialogue.
Want upping your game, get system with Dolby Atmos. Those that got speaker that makes sound as if coming from top.
2.0 or 2.1 sucks if your movie is 5.1 audio, especially action movie. If don't put loud enough, voice hard to hear. If put loud enough, action scene become too loud. Unless your player can adjust the mixing to apply higher gain for center audio.
If not action movie then 2.0 or 2.1 still ok.

Some newer soundbar got impressive number of speaker in it and can give enough distinction for sound in middle (dialogue) and side, plus back and top.

USB for music? As in USB drive with music files? Use bluetooth much easier. If the speaker support APTX HD or LDAC, can go for it to use bluetoooth. Pair it with your handphone or tablet.

5.1 speaker or soundbar is quite pricey. Not sure can get below 2.5k
Long time never check about home theater speaker so not sure what is the latest bang for buck speaker.
Can try ask at this thread link since they know more about home theater set.
https://forum.lowyat.net/topic/3067159/+3860
https://forum.lowyat.net/topic/3863469/+2140

This post has been edited by xxboxx: Sep 28 2021, 11:10 PM

Change to speaker with bigger main drive, 5.5" or 6.5".
The s351db should also give better sub-bass, but the sub placement is very important.

Maybe some where there's wire connection that loose.

Try find Edifier S1000DB, sometimes will pop out. Usually can get below 1k

If can get Wharfedale Diamond 12.1 is also good.

It does, I use before for desktop 4" and then 5", the sub-bass sounds more deep with 5". Or S350 since it is 2.1. If you don't priority much for bass, Diamond 12.0 is what I would pick from the list.

If important is music, get S3000 PRO. If all equal or more on movie, sound bar with sub-woofer.

Pebble V3 using 2.25" driver, 8W RMS. T60 using 2.75" driver, 30W RMS. T60 will be better. But both is nothing if compare with R1700BT, it have 9mm dome tweeter and 4" bass driver.

If I were you, I'll upgrade living room speaker and use R1700BT for desktop.

Lazada or shopee got sell speaker stand. Search for bookshelf speaker stand. Some seller have list of different height stand, so you can match with your speaker height and listening position.

Since you already have the bluetooth receiver, try it first.

I think both is too small for living room. 5" or better 8" speaker more suitable.

Also check Carousel, more normal seller, not just audiophile. There's also some used hifi shops selling there.