Creating creature sounds is a great example of sound design because you have to create imaginary sounds. In LOTR the sound of the Balrogs flaming roar (the bridge scene in the Moria Mines) is composed of a cinder block dragged across a concrete floor - loaded into a sampler and pitched down - and a WWI era flame thrower plus other elements.
The "thunk" is a lot better as are the finger taps. The cell phone needs more "snap" (personal preference). Bring up the volume on the other elements - we're auditioning the sounds right now, not fitting them into the puzzle of the final mix. The mix is a completely different topic.
Doing Foley can be a PITA, but is a lot easier if you are set up properly and have the right approach, which can be very personal. Besides having a really nice mic and pre-amp (I know, you can't afford that right now but they make a huge difference, they can really capture subtleties) you need to build a substantial props collection.
Part of great Foley work is understanding the characters. I don't have the ability switch in and out of characters like the professional Foley walkers do, so I do each character all they way through a project. I start with footsteps, then do a cloth pass and then do the props.
No matter what approach you take you need to be highly organized, just like you do with your production shot list and shooting schedule. For example, "John" walks on wood floors in scenes 2, 7, 9, 15 and 36, carpet in scenes 3, 12, 19 and 29, concrete in scenes 4, 21, 22, and 31, and on grass/dirt in scenes 5, 27, 33 and 34. You also have to note what footwear he's using. Then the list shows the types of cloth and the handled props.
I pick the appropriate footwear and set up the wood floors, then do the carpet, etc. This way I'm not constantly changing the surfaces (I don't have Foley pits). Then I'll clean up and collect all of the props for the cloth pass, clean up again and do the props/handling pass. This way I'm entirely into the personality of one character for the length of the project and the Foley is consistent with him/her, and I'm organized so I'm not wasting time.
Keep doing what you're doing; you're learning a lot and you'll get better as you go along. It's an art form just like any other. I know that I always start off slowly, but the pace picks up as I get into the process.
BTW, go to YouTube and search Sound Design for King Kong. There are seven or eight pretty good videos on the process. Ric Viers - who wrote the "Sound FX Bible" (which you should get) - has dozens of videos on YT as well. He interviews other biggies of the audio post world like Vanessa Ament (who wrote "The Foley Grail", another must have), David Sonnenschien (who wrote "Sound Design: The Expressive Power of Music, Voice and Sound Effects in Cinema", another great book) and Charles Maynes (the current "God" of recording weapons for films and video games) in addition to his many "Chop Shop" and Rode Rage (yes, for the folks at Rode mics) sound recording vids.
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