Charts for Base Stats?

>a near perfect lower level mon is better (i.e Has more stats overall) than a very low IV higher level mon.
Generally no. At the same CP and the same IV spread (ie. if you had a 0/0/0 and a 15/15/15 at the same CP), the stats will be roughly equal for most pokemon. (Edited)
>Does a pokemon really go up in base stats that much in just 2.5 levels?
Yes.
>is level also considered in CP calculation?
Level modifies stats and CP is calculated from stats, so indirectly yes.

Here's a solid calculator for stats https://pokemonpvp.club/pvp/iv
There are also numerous spreadsheets you can find on TSR that list the best sets of PvP IVs or calculate your stat product with given IVs.

Well, first, base stats don't change.

Each stat is:
(base stat + IV) * CPM

The CP multiplier increases with the level, and that scales the stats.

https://pokemongo.gamepress.gg/pokemon-stats-advanced

Second, try a search on the Silph Road reddit for "PVP IV spreadsheet" as a starting point.

Generally speaking, higher defense IV and lower attack IV will give more total stats.