Well.. in the ranger animal companion section it clearly sais what animal companion can I choose... in the core rulebook I mean^^ Can I use different animal companions? Where is it written?^^
Rocs taken as animal companions by druids or rangers are typically newly hatched birds—a baby roc is the size of a person and ready for flight and hunting within minutes of hatching. Unfortunately for druids seeking animal companions of legendary size, an animal companion roc is limited to Large size—still large enough for a Medium druid or ranger to use the flying beast as a mount.
First of all thanks for the help xD
Second of all I know that's incredibly suboptimal but I tried to make it optimal (with bow, cheetah and so on...) but then, when I picture my dwarf with the bow, the falchion and the cheetah... well... I just couldn't see it xD I'm lucky that in my group the plain optimization isn't that important (we still try to make strong PCs but we accept having PCs a little less stronger but more interesting^^) so I really prefer having a PC that I like than a strong one... and, even if it's suboptimal, I don't think that my dwarf is that weak^^ I'm I wrong?
Speaking of the build... why is IPS so important? Will there be that much enemies with concealment? I ask because I've never played ranged characters so I'm not used to chek stuff like that xD
About the armor... I know that having a +1 armor and a +1 buckler helps me save some money, but since I'm going in melee from time to time, losing 1 AC (with the normal buckler) or 2 (with the +1 buckler) it's different^^ And I know that, expecially with the crossbow build, switch hitting is really worse than suboptimal but, as I said before, we have only one melee fighter and so, even if I will use my crossbow most of the time, I really need to be able to switch to melee if necessary. I used only one feat for the melee (power attack) so I don't think I wasted to many resources on my melee capacity...
And I'm not going to go in melee to often... just when really needed^^
Last but not least the animal companion. I imagine you're talking about the cheetah as better companion... well... I've already made a sheet for the cheetah and I know that it has better AC, 3 attacks, the trip ability, more initiative, more speed and with the appropriate feats (weapon finesse and agile maneuvers) better CMB and to hit bonus... but it's too damned skinny! I have my short, muscular, rude, bearded, almost always drunk dwarf with sigars, a greataxe and a f*****g big crossbow... whit a skinny cat on his side? It hurts my feeling more than having a bow xD Isn't there a way to make my dog a better companion (different feats/skills/abilities) instead of changing it? Or a way to have a better companion instead of the dog but still heavy, rude end massive?^^ I would have gone to the boar or the bison (or even the rhino xD) but I can't have them since I'm a ranger and not a druid...
It's not how weak the build is, it's the fact that things will get worse with level. You've basically shut yourself off forever from the other basic archery feats. The cost of maintaining two good weapons will severely pinch your finances as you get higher. And so forth.
IPS is hugely important. Concealment is common, but it does so much more than that. It also ignores less than total cover. Even if the DM never uses terrain for cover, just the simple act of shooting at an enemy with an ally standing between the two of you gives that enemy soft cover (and an effective +4 AC). Finally, IPS also lets you shoot into a grapple without possibly killing your friend. It's a great feat, and the fact ranger can get it FIVE levels early is really awesome!
You can get by without it, but I personally love it and try to get it ASAP.
Armor: How about this, then? Upgrading +1 armor to +2 costs 3000 gp. Use that money instead to get a ring of protection +1 (which adds to your touch AC, on top of overall AC) and Cloak of Resistance +1. You come out much better.
I REALLY like the Roc and the various dinosaurs (T-Rex and Allosaurus are incredible).
That said, I recommend the Arsinoitherium (mega fauna rino) or the T-Rex or the stegosaurus

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.