Assuming I don't suck playing one.
If you take generally useful feats in addition to Natural Spell -- an item creation, a metamagic, and stuff to enhance your Summoning spells, for example -- then the only thing you can suck at are things you can change day to day.
1/ Spell Selection. This can be hard. You will want to spend some time figuring out which spells to put in items (scrolls & wands) and which ones to prepare, and you will be wrong about more than a few of them. But
even if you suck at this, it only hurts until you learn better. You can learn and put your new knowledge to work the very next day.
2/ Animal Stats. This isn't hard, but it's time-consuming.
3/ Tactics. You have a
lot of options in combat. Applying them well will take time, but again, you're going to be able to use what you learn almost immediately.
Bonus feats for druids as like for fighters? Or do you mean that I get more out of it than other classes?
What I meant was that, when you take the form of an animal, you get that animal's bonus feats... except it looks like now you don't.
You only get free access to feats when you turn into an Elemental starting at level 16. So don't worry about it, I was wrong here.
I get Natural Spell (was on my list anyway

), Spell Focus (Summoning) and Augment Summoning, but the other ones... Is Extend Spell intended for summons? Not sure if the fights last longer than 9 rounds.

Empower Spell: Do druids have enough spells left after summoning allies to make this feat worthwhile? Quicken Spell... If I have the double number of feats, maybe, but right now too much competition to consider. And why Scribe Scroll? Isn't that something more suitable for wizards?
Wizards get Scribe Scroll for free, and no, it's best for Clerics and Druids. See, you get FULL ACCESS to your whole spell list. If you have a week of down-time, you can prep any spell in the book, even if it's not a spell you would normally prepare.
Water breathing, for example. A Wizard would need to spend gold just to have access to that spell (or take it as one of his very limited 2/level free spells). You get access to it automatically at 5th level, but you won't prepare it regularly unless you're going on a boat trip. So scribe yourself a couple scrolls of
water breathing (level 6 so it'll last for 12 hours) and keep them in your back pocket, then whip them out when you unexpectedly need to fight in / search / traverse a body of water.
When you read through the spell list and think "oh that's nice but ...", you've found a candidate for scribing.
On the subject of item creation, you will want a wand of
lesser restoration and several wands of
cure light wounds.
- - -
Extend Spell does work on summoning spells, but I was more thinking about it for buffs like
greater magic fang and
barkskin and
longstrider.
Empower Spell works with your big boom spells like
call lightning and
flame strike.
Remember that you never need to prepare summoning spells, since you can convert any prepared spell into a
summon nature's ally of the same level.
Cheers, -- N