Innodb vs. myisam storage usage *shocked*

[Consensus]

Hello,
Short introduction : (:-)
I was shocked by the myisam repair (i created a automated repair using myisamchk which tries from softest to hardest repair until it works)
After a power outage during write the chance is 1: about 50 that the repair will not only repair the table it almost all records gets deleted. i had results from 1 records up to 300,000 records which got removed (and those were not buggy)

On freenode i got the hint to use Innodb, it got doublewrite buffers etc, and should handle a crash much better.

I did a few tests and i am "stopped" by the result that innodb required up to 8 times of the storage myisam needs!!

I got a table with 2 date fields 1 datetime and integers (tiny,small,medium,normal),
the primary key (no other index) is on 2 INT columns, the last integer is autoincremental.
total of 32 columns (most can be null)
Rowformat is dynamic.

I filled it with dummy data (300,000 rows, few numbers and NULLs).

Result :

myisam:
Datafile = 13mb
Index = 7mb

i converted it now using alter table type=innodb

innodb:
Datafile = 90mb (!!!!!)
Datalength = 53mb
Indexlength = 6.6mb
Freespace = 17.5mb (?)


I use mysqld 4.0.16

Maybe someone here got a few spare minutes and can help me a bit
Is this really normal behaviour of innodb?
Is there a way to make the storage use more efficient?
Is there any other option for me, i do not need transactions or ultra performance.
I just need something like myisam but it needs to handle a crash (power loss) better
than myisam (removing 90% of the table because of 1 corrupted row is way too much)

Please respond