After experimenting with a long running average at maxed out FPS and a variety of map sizes, 128 seems to actually be a good size to use if only drawing bits of world with stuff in it. 64 actually did even better in some situations, but significantly worse in others (lots of land, zoomed out).
/*
** $Id: lmem.h,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
** Interface to Memory Manager
** See Copyright Notice in lua.h
*/
#ifndef lmem_h
#define lmem_h
#include <stddef.h>
#include "llimits.h"
#include "lua.h"
#define MEMERRMSG "not enough memory"
#define luaM_reallocv(L,b,on,n,e) \
((cast(size_t, (n)+1) <= MAX_SIZET/(e)) ? /* +1 to avoid warnings */ \
luaM_realloc_(L, (b), (on)*(e), (n)*(e)) : \
luaM_toobig(L))
#define luaM_freemem(L, b, s) luaM_realloc_(L, (b), (s), 0)
#define luaM_free(L, b) luaM_realloc_(L, (b), sizeof(*(b)), 0)
#define luaM_freearray(L, b, n, t) luaM_reallocv(L, (b), n, 0, sizeof(t))
#define luaM_malloc(L,t) luaM_realloc_(L, NULL, 0, (t))
#define luaM_new(L,t) cast(t *, luaM_malloc(L, sizeof(t)))
#define luaM_newvector(L,n,t) \
cast(t *, luaM_reallocv(L, NULL, 0, n, sizeof(t)))
#define luaM_growvector(L,v,nelems,size,t,limit,e) \
if ((nelems)+1 > (size)) \
((v)=cast(t *, luaM_growaux_(L,v,&(size),sizeof(t),limit,e)))
#define luaM_reallocvector(L, v,oldn,n,t) \
((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t))))
LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize,
size_t size);
LUAI_FUNC void *luaM_toobig (lua_State *L);
LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int *size,
size_t size_elem, int limit,
const char *errormsg);
#endif