Both shape and nature manipulation are types of molding chakra whereas one deal with one thing and other with other. You got my point. Anyhow what I said already by mixing our physical and spiritual energies we will create chakra which we can release from one of our 361 tenketsus. Now when we are releasing this chakra we usually apply processes of nature and shape manipulation. Nature manipulation deals with transforming chakra into specific element with different characteristics. Now depending on the element into which you are transforming this chakra you would focus on different aspects. On the other hand there is shape manipulation which deals with actual form that chakra takes. This can be anything and it also depends on the technique and/or element which is in question.
In my opinion, fire is one impulsive element as well as a precarious one, that can easily smoulder and suddenly burst. The flames of creativity and passion, dancing source of heat, life and light. Fire is capable of giving wings of fortitude, benevolence and devotion. Fire is adamant and exhilarating and doubtlessly not subtle. It is seen as a force that is burning inside all of us, giving us iron willpower as to reach our objective, bestowing upon us the passion to do it with all of ourselves. What I learned is that water is stronger then fire. This being said, a C ranked water jutsu is equivalent in power as a B ranked fire jutsu, keeping in mind that sizes of jutsus are approximately the same. This is because water is capable of extinguishing flames and thus not letting them keep on burning. Although water is stronger then fire, when used in conjuction, the two are capable of forming steam. This is especially usable if you are a sensory ninja or are capable to in any way or form know where your opponent is standing. You will be capable of hiding your presence and thus create sneak attacks. Now if you know that your opponent is capable of sensing you could get rid of the steam by releasing wind which will passively blow away the steam as it continues towards opponent. Now when it comes to fire release and wind release. Fire is stronger then wind, because oxygen from which wind is formed is just going to fuel the flames. Although when they clash fire is going to overpower wind, they are actually quite great when it comes to their combo usage. Oxygen from which wind is formed is going to fuel flames even more and thus make them stronger and make them effect bigger area. The speed of the technique that would now be running would be greater. Fire and Earth Release in our RP are neutral with each other. Which means that a C ranked fire technique will be equivalent in power as a C ranked earth technique, keeping in mind that their size is approximately the same. Although they are neutral to each other when they clash they are quite good when they combine with each other. The hotnes from fire will effect the earth and thus melt it forming magma. Keep in mind that magma will be formed if earth is more solid. If the variation of earth release, mud was combined with fire release, hotness of fire is going to harden the mud. Same as with Earth Release, Fire and Lighting are neutral once they clash. It is usally great to make great damage to opponent. Fire release is going to burn down the opponent whereas lighting is going to shock opponent. Interesting to the two is that they in a way compensate each other. Fire is strong against Wind whereas, Lighting is weak against Wind. It would be good to let's say firstly send a lighting attack as a bait, assuming that opponent is going to use wind jutsu as you send a fire attack to follow it.
Any questions?