Complete 5.1 system Samsung vs separate amp+speakers

upgrading from a HTIB based set to a separate receiver and speakers is certainly the way to go if you want more (and better) speaker choices as well as better support for multiple inputs (like pc, consoles, etcetera)

another option: instead of buying a cheap set of speakers and then replacing them, you could always buy a partial set from the speaker vendor of your choice. for instance you can start out buying just two front speakers (2.0) then buy more as you can afford. or start with a 2.1 or 3.1 depending on your budget. in this way you can put more money towards what you really want instead of wasting it on a product you will only get rid of. keep in mind if you do this route i would buy it only a few years at most so the speakers you want are still available on the market.

if that is not an option, you could go with your original plan. do double check that the receiver you plan on purchasing is rated to handle the speaker power of the models you want to buy (watts per channel at ohm impedence level for the speakers). generally receivers can handle speakers at 6&8ohm impedance loads (some at 4) and have listed maximum watts per channel (wpc) for each available ohm rating you can use as a go-by. i cannot say if the jamos are going to be better than what you have now however jamo generally gets a thumbs up in terms of how they sound for the money and i would think they should be fine. as always - listening in person is the only way to know for sure if you prefer them over what you have now.