First, I must caution that it's been around 3 years since I last played Eschalon Book 1, so I deny any responsibilty to the effectiveness of the following advice.
In my opinion, it is better to specialize. Book 1 isn't overly difficult, but if you spead your skill points too much, you're probably going to have a tough time by the latter half of the game. However, you don't have to completely min-max your character, the points aren't that sparse, there is room for some generalization. There are also skill books in the world, so some skills can be gained "free" via these. Protip: Opening a skill costs 3 points, IIRC, but raising an open/learned skill by a level costs 1 point, regardless of level. So, it's very effective to open skills via skill books as you save points this way. Of course, the problem is actually finding the books…
Playing a ranger can get ardorous as arrows weigh quite much (could even be as silly as 1 pound each, can't remember), so you'll quickly reach your ENC limit with just a hefty bundle of arrows leaving little room for loot. Also, the merchants' supplies of arrows aren't guaranteed; I recall having a real problem with that when the merchants didn't restock on arrows very fast. Kiting, of sorts, is quite effective, however, so it's good to carry a bow if you're a melee fighter, to soften your foes up before close combat (and to kill certain acid creatures which can destroy you equipment).
A pure melee fighter is bound to be dull in the long run, as the game has very simplistic melee combat (this was improved a little, but not much, in Book 2). Unless you really like "I hit, you hit, I hit, you hit" type of combat, it's better to steer away from pure melee. Of course, the same could be said of many other CRPGs, but in Eschalon pure melee combat is particularly boring, IMO. This coming from a guy who regularly plays and likes roguelikes, which
at their base have similar styled combat. I can't put my finger on why Book 1 melee combat is so dull, maybe it's the scarcity of different types of enemies (lack of variety) or the general slowness of it with too much missing or hitting for puny amounts of damage (combat drags on too long). CAn't remember, it's been awhile, but I still remember being quite bored with melee combat in Eschalon Book 1.
Note that in order to have a minimap, you must have at least one point in Cartography. More points in it increases the fidelity of the map. There is a skill book on Cartography so if you're fine with a pretty rudimentary map (but good enough to navigate by), don't put too many points in it. However, if you want a pretty and fully filled minimap, then you need to put some extra points in Cartography.
(Sorry have to stop. At work and have to go.)